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1894 lines
41 KiB
1894 lines
41 KiB
#include "cache.h" |
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#include "run-command.h" |
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#include "exec-cmd.h" |
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#include "sigchain.h" |
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#include "strvec.h" |
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#include "thread-utils.h" |
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#include "strbuf.h" |
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#include "string-list.h" |
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#include "quote.h" |
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#include "config.h" |
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|
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void child_process_init(struct child_process *child) |
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{ |
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memset(child, 0, sizeof(*child)); |
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strvec_init(&child->args); |
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strvec_init(&child->env_array); |
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} |
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|
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void child_process_clear(struct child_process *child) |
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{ |
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strvec_clear(&child->args); |
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strvec_clear(&child->env_array); |
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} |
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|
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struct child_to_clean { |
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pid_t pid; |
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struct child_process *process; |
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struct child_to_clean *next; |
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}; |
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static struct child_to_clean *children_to_clean; |
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static int installed_child_cleanup_handler; |
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|
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static void cleanup_children(int sig, int in_signal) |
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{ |
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struct child_to_clean *children_to_wait_for = NULL; |
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|
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while (children_to_clean) { |
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struct child_to_clean *p = children_to_clean; |
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children_to_clean = p->next; |
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|
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if (p->process && !in_signal) { |
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struct child_process *process = p->process; |
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if (process->clean_on_exit_handler) { |
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trace_printf( |
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"trace: run_command: running exit handler for pid %" |
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PRIuMAX, (uintmax_t)p->pid |
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); |
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process->clean_on_exit_handler(process); |
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} |
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} |
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|
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kill(p->pid, sig); |
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|
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if (p->process && p->process->wait_after_clean) { |
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p->next = children_to_wait_for; |
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children_to_wait_for = p; |
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} else { |
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if (!in_signal) |
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free(p); |
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} |
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} |
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|
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while (children_to_wait_for) { |
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struct child_to_clean *p = children_to_wait_for; |
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children_to_wait_for = p->next; |
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|
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while (waitpid(p->pid, NULL, 0) < 0 && errno == EINTR) |
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; /* spin waiting for process exit or error */ |
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|
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if (!in_signal) |
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free(p); |
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} |
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} |
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|
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static void cleanup_children_on_signal(int sig) |
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{ |
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cleanup_children(sig, 1); |
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sigchain_pop(sig); |
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raise(sig); |
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} |
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|
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static void cleanup_children_on_exit(void) |
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{ |
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cleanup_children(SIGTERM, 0); |
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} |
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|
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static void mark_child_for_cleanup(pid_t pid, struct child_process *process) |
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{ |
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struct child_to_clean *p = xmalloc(sizeof(*p)); |
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p->pid = pid; |
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p->process = process; |
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p->next = children_to_clean; |
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children_to_clean = p; |
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|
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if (!installed_child_cleanup_handler) { |
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atexit(cleanup_children_on_exit); |
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sigchain_push_common(cleanup_children_on_signal); |
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installed_child_cleanup_handler = 1; |
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} |
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} |
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|
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static void clear_child_for_cleanup(pid_t pid) |
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{ |
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struct child_to_clean **pp; |
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|
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for (pp = &children_to_clean; *pp; pp = &(*pp)->next) { |
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struct child_to_clean *clean_me = *pp; |
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|
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if (clean_me->pid == pid) { |
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*pp = clean_me->next; |
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free(clean_me); |
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return; |
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} |
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} |
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} |
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|
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static inline void close_pair(int fd[2]) |
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{ |
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close(fd[0]); |
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close(fd[1]); |
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} |
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|
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int is_executable(const char *name) |
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{ |
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struct stat st; |
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|
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if (stat(name, &st) || /* stat, not lstat */ |
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!S_ISREG(st.st_mode)) |
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return 0; |
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|
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#if defined(GIT_WINDOWS_NATIVE) |
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/* |
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* On Windows there is no executable bit. The file extension |
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* indicates whether it can be run as an executable, and Git |
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* has special-handling to detect scripts and launch them |
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* through the indicated script interpreter. We test for the |
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* file extension first because virus scanners may make |
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* it quite expensive to open many files. |
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*/ |
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if (ends_with(name, ".exe")) |
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return S_IXUSR; |
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|
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{ |
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/* |
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* Now that we know it does not have an executable extension, |
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* peek into the file instead. |
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*/ |
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char buf[3] = { 0 }; |
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int n; |
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int fd = open(name, O_RDONLY); |
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st.st_mode &= ~S_IXUSR; |
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if (fd >= 0) { |
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n = read(fd, buf, 2); |
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if (n == 2) |
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/* look for a she-bang */ |
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if (!strcmp(buf, "#!")) |
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st.st_mode |= S_IXUSR; |
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close(fd); |
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} |
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} |
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#endif |
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return st.st_mode & S_IXUSR; |
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} |
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|
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/* |
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* Search $PATH for a command. This emulates the path search that |
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* execvp would perform, without actually executing the command so it |
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* can be used before fork() to prepare to run a command using |
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* execve() or after execvp() to diagnose why it failed. |
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* |
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* The caller should ensure that file contains no directory |
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* separators. |
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* |
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* Returns the path to the command, as found in $PATH or NULL if the |
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* command could not be found. The caller inherits ownership of the memory |
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* used to store the resultant path. |
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* |
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* This should not be used on Windows, where the $PATH search rules |
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* are more complicated (e.g., a search for "foo" should find |
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* "foo.exe"). |
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*/ |
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static char *locate_in_PATH(const char *file) |
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{ |
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const char *p = getenv("PATH"); |
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struct strbuf buf = STRBUF_INIT; |
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|
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if (!p || !*p) |
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return NULL; |
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|
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while (1) { |
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const char *end = strchrnul(p, ':'); |
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|
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strbuf_reset(&buf); |
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|
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/* POSIX specifies an empty entry as the current directory. */ |
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if (end != p) { |
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strbuf_add(&buf, p, end - p); |
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strbuf_addch(&buf, '/'); |
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} |
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strbuf_addstr(&buf, file); |
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|
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if (is_executable(buf.buf)) |
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return strbuf_detach(&buf, NULL); |
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|
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if (!*end) |
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break; |
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p = end + 1; |
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} |
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|
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strbuf_release(&buf); |
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return NULL; |
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} |
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|
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static int exists_in_PATH(const char *file) |
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{ |
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char *r = locate_in_PATH(file); |
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int found = r != NULL; |
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free(r); |
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return found; |
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} |
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|
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int sane_execvp(const char *file, char * const argv[]) |
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{ |
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#ifndef GIT_WINDOWS_NATIVE |
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/* |
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* execvp() doesn't return, so we all we can do is tell trace2 |
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* what we are about to do and let it leave a hint in the log |
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* (unless of course the execvp() fails). |
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* |
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* we skip this for Windows because the compat layer already |
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* has to emulate the execvp() call anyway. |
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*/ |
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int exec_id = trace2_exec(file, (const char **)argv); |
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#endif |
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|
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if (!execvp(file, argv)) |
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return 0; /* cannot happen ;-) */ |
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|
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#ifndef GIT_WINDOWS_NATIVE |
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{ |
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int ec = errno; |
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trace2_exec_result(exec_id, ec); |
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errno = ec; |
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} |
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#endif |
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|
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/* |
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* When a command can't be found because one of the directories |
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* listed in $PATH is unsearchable, execvp reports EACCES, but |
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* careful usability testing (read: analysis of occasional bug |
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* reports) reveals that "No such file or directory" is more |
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* intuitive. |
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* |
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* We avoid commands with "/", because execvp will not do $PATH |
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* lookups in that case. |
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* |
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* The reassignment of EACCES to errno looks like a no-op below, |
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* but we need to protect against exists_in_PATH overwriting errno. |
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*/ |
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if (errno == EACCES && !strchr(file, '/')) |
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errno = exists_in_PATH(file) ? EACCES : ENOENT; |
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else if (errno == ENOTDIR && !strchr(file, '/')) |
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errno = ENOENT; |
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return -1; |
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} |
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|
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static const char **prepare_shell_cmd(struct strvec *out, const char **argv) |
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{ |
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if (!argv[0]) |
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BUG("shell command is empty"); |
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|
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if (strcspn(argv[0], "|&;<>()$`\\\"' \t\n*?[#~=%") != strlen(argv[0])) { |
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#ifndef GIT_WINDOWS_NATIVE |
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strvec_push(out, SHELL_PATH); |
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#else |
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strvec_push(out, "sh"); |
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#endif |
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strvec_push(out, "-c"); |
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|
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/* |
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* If we have no extra arguments, we do not even need to |
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* bother with the "$@" magic. |
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*/ |
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if (!argv[1]) |
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strvec_push(out, argv[0]); |
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else |
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strvec_pushf(out, "%s \"$@\"", argv[0]); |
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} |
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|
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strvec_pushv(out, argv); |
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return out->v; |
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} |
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|
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#ifndef GIT_WINDOWS_NATIVE |
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static int child_notifier = -1; |
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|
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enum child_errcode { |
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CHILD_ERR_CHDIR, |
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CHILD_ERR_DUP2, |
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CHILD_ERR_CLOSE, |
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CHILD_ERR_SIGPROCMASK, |
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CHILD_ERR_ENOENT, |
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CHILD_ERR_SILENT, |
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CHILD_ERR_ERRNO |
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}; |
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|
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struct child_err { |
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enum child_errcode err; |
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int syserr; /* errno */ |
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}; |
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|
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static void child_die(enum child_errcode err) |
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{ |
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struct child_err buf; |
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|
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buf.err = err; |
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buf.syserr = errno; |
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|
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/* write(2) on buf smaller than PIPE_BUF (min 512) is atomic: */ |
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xwrite(child_notifier, &buf, sizeof(buf)); |
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_exit(1); |
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} |
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|
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static void child_dup2(int fd, int to) |
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{ |
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if (dup2(fd, to) < 0) |
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child_die(CHILD_ERR_DUP2); |
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} |
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|
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static void child_close(int fd) |
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{ |
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if (close(fd)) |
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child_die(CHILD_ERR_CLOSE); |
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} |
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|
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static void child_close_pair(int fd[2]) |
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{ |
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child_close(fd[0]); |
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child_close(fd[1]); |
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} |
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|
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/* |
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* parent will make it look like the child spewed a fatal error and died |
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* this is needed to prevent changes to t0061. |
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*/ |
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static void fake_fatal(const char *err, va_list params) |
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{ |
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vreportf("fatal: ", err, params); |
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} |
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|
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static void child_error_fn(const char *err, va_list params) |
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{ |
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const char msg[] = "error() should not be called in child\n"; |
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xwrite(2, msg, sizeof(msg) - 1); |
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} |
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|
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static void child_warn_fn(const char *err, va_list params) |
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{ |
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const char msg[] = "warn() should not be called in child\n"; |
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xwrite(2, msg, sizeof(msg) - 1); |
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} |
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|
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static void NORETURN child_die_fn(const char *err, va_list params) |
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{ |
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const char msg[] = "die() should not be called in child\n"; |
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xwrite(2, msg, sizeof(msg) - 1); |
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_exit(2); |
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} |
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|
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/* this runs in the parent process */ |
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static void child_err_spew(struct child_process *cmd, struct child_err *cerr) |
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{ |
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static void (*old_errfn)(const char *err, va_list params); |
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|
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old_errfn = get_error_routine(); |
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set_error_routine(fake_fatal); |
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errno = cerr->syserr; |
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|
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switch (cerr->err) { |
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case CHILD_ERR_CHDIR: |
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error_errno("exec '%s': cd to '%s' failed", |
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cmd->argv[0], cmd->dir); |
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break; |
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case CHILD_ERR_DUP2: |
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error_errno("dup2() in child failed"); |
|
break; |
|
case CHILD_ERR_CLOSE: |
|
error_errno("close() in child failed"); |
|
break; |
|
case CHILD_ERR_SIGPROCMASK: |
|
error_errno("sigprocmask failed restoring signals"); |
|
break; |
|
case CHILD_ERR_ENOENT: |
|
error_errno("cannot run %s", cmd->argv[0]); |
|
break; |
|
case CHILD_ERR_SILENT: |
|
break; |
|
case CHILD_ERR_ERRNO: |
|
error_errno("cannot exec '%s'", cmd->argv[0]); |
|
break; |
|
} |
|
set_error_routine(old_errfn); |
|
} |
|
|
|
static int prepare_cmd(struct strvec *out, const struct child_process *cmd) |
|
{ |
|
if (!cmd->argv[0]) |
|
BUG("command is empty"); |
|
|
|
/* |
|
* Add SHELL_PATH so in the event exec fails with ENOEXEC we can |
|
* attempt to interpret the command with 'sh'. |
|
*/ |
|
strvec_push(out, SHELL_PATH); |
|
|
|
if (cmd->git_cmd) { |
|
prepare_git_cmd(out, cmd->argv); |
|
} else if (cmd->use_shell) { |
|
prepare_shell_cmd(out, cmd->argv); |
|
} else { |
|
strvec_pushv(out, cmd->argv); |
|
} |
|
|
|
/* |
|
* If there are no dir separator characters in the command then perform |
|
* a path lookup and use the resolved path as the command to exec. If |
|
* there are dir separator characters, we have exec attempt to invoke |
|
* the command directly. |
|
*/ |
|
if (!has_dir_sep(out->v[1])) { |
|
char *program = locate_in_PATH(out->v[1]); |
|
if (program) { |
|
free((char *)out->v[1]); |
|
out->v[1] = program; |
|
} else { |
|
strvec_clear(out); |
|
errno = ENOENT; |
|
return -1; |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static char **prep_childenv(const char *const *deltaenv) |
|
{ |
|
extern char **environ; |
|
char **childenv; |
|
struct string_list env = STRING_LIST_INIT_DUP; |
|
struct strbuf key = STRBUF_INIT; |
|
const char *const *p; |
|
int i; |
|
|
|
/* Construct a sorted string list consisting of the current environ */ |
|
for (p = (const char *const *) environ; p && *p; p++) { |
|
const char *equals = strchr(*p, '='); |
|
|
|
if (equals) { |
|
strbuf_reset(&key); |
|
strbuf_add(&key, *p, equals - *p); |
|
string_list_append(&env, key.buf)->util = (void *) *p; |
|
} else { |
|
string_list_append(&env, *p)->util = (void *) *p; |
|
} |
|
} |
|
string_list_sort(&env); |
|
|
|
/* Merge in 'deltaenv' with the current environ */ |
|
for (p = deltaenv; p && *p; p++) { |
|
const char *equals = strchr(*p, '='); |
|
|
|
if (equals) { |
|
/* ('key=value'), insert or replace entry */ |
|
strbuf_reset(&key); |
|
strbuf_add(&key, *p, equals - *p); |
|
string_list_insert(&env, key.buf)->util = (void *) *p; |
|
} else { |
|
/* otherwise ('key') remove existing entry */ |
|
string_list_remove(&env, *p, 0); |
|
} |
|
} |
|
|
|
/* Create an array of 'char *' to be used as the childenv */ |
|
ALLOC_ARRAY(childenv, env.nr + 1); |
|
for (i = 0; i < env.nr; i++) |
|
childenv[i] = env.items[i].util; |
|
childenv[env.nr] = NULL; |
|
|
|
string_list_clear(&env, 0); |
|
strbuf_release(&key); |
|
return childenv; |
|
} |
|
|
|
struct atfork_state { |
|
#ifndef NO_PTHREADS |
|
int cs; |
|
#endif |
|
sigset_t old; |
|
}; |
|
|
|
#define CHECK_BUG(err, msg) \ |
|
do { \ |
|
int e = (err); \ |
|
if (e) \ |
|
BUG("%s: %s", msg, strerror(e)); \ |
|
} while(0) |
|
|
|
static void atfork_prepare(struct atfork_state *as) |
|
{ |
|
sigset_t all; |
|
|
|
if (sigfillset(&all)) |
|
die_errno("sigfillset"); |
|
#ifdef NO_PTHREADS |
|
if (sigprocmask(SIG_SETMASK, &all, &as->old)) |
|
die_errno("sigprocmask"); |
|
#else |
|
CHECK_BUG(pthread_sigmask(SIG_SETMASK, &all, &as->old), |
|
"blocking all signals"); |
|
CHECK_BUG(pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &as->cs), |
|
"disabling cancellation"); |
|
#endif |
|
} |
|
|
|
static void atfork_parent(struct atfork_state *as) |
|
{ |
|
#ifdef NO_PTHREADS |
|
if (sigprocmask(SIG_SETMASK, &as->old, NULL)) |
|
die_errno("sigprocmask"); |
|
#else |
|
CHECK_BUG(pthread_setcancelstate(as->cs, NULL), |
|
"re-enabling cancellation"); |
|
CHECK_BUG(pthread_sigmask(SIG_SETMASK, &as->old, NULL), |
|
"restoring signal mask"); |
|
#endif |
|
} |
|
#endif /* GIT_WINDOWS_NATIVE */ |
|
|
|
static inline void set_cloexec(int fd) |
|
{ |
|
int flags = fcntl(fd, F_GETFD); |
|
if (flags >= 0) |
|
fcntl(fd, F_SETFD, flags | FD_CLOEXEC); |
|
} |
|
|
|
static int wait_or_whine(pid_t pid, const char *argv0, int in_signal) |
|
{ |
|
int status, code = -1; |
|
pid_t waiting; |
|
int failed_errno = 0; |
|
|
|
while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR) |
|
; /* nothing */ |
|
if (in_signal) { |
|
if (WIFEXITED(status)) |
|
code = WEXITSTATUS(status); |
|
return code; |
|
} |
|
|
|
if (waiting < 0) { |
|
failed_errno = errno; |
|
error_errno("waitpid for %s failed", argv0); |
|
} else if (waiting != pid) { |
|
error("waitpid is confused (%s)", argv0); |
|
} else if (WIFSIGNALED(status)) { |
|
code = WTERMSIG(status); |
|
if (code != SIGINT && code != SIGQUIT && code != SIGPIPE) |
|
error("%s died of signal %d", argv0, code); |
|
/* |
|
* This return value is chosen so that code & 0xff |
|
* mimics the exit code that a POSIX shell would report for |
|
* a program that died from this signal. |
|
*/ |
|
code += 128; |
|
} else if (WIFEXITED(status)) { |
|
code = WEXITSTATUS(status); |
|
} else { |
|
error("waitpid is confused (%s)", argv0); |
|
} |
|
|
|
clear_child_for_cleanup(pid); |
|
|
|
errno = failed_errno; |
|
return code; |
|
} |
|
|
|
static void trace_add_env(struct strbuf *dst, const char *const *deltaenv) |
|
{ |
|
struct string_list envs = STRING_LIST_INIT_DUP; |
|
const char *const *e; |
|
int i; |
|
int printed_unset = 0; |
|
|
|
/* Last one wins, see run-command.c:prep_childenv() for context */ |
|
for (e = deltaenv; e && *e; e++) { |
|
struct strbuf key = STRBUF_INIT; |
|
char *equals = strchr(*e, '='); |
|
|
|
if (equals) { |
|
strbuf_add(&key, *e, equals - *e); |
|
string_list_insert(&envs, key.buf)->util = equals + 1; |
|
} else { |
|
string_list_insert(&envs, *e)->util = NULL; |
|
} |
|
strbuf_release(&key); |
|
} |
|
|
|
/* "unset X Y...;" */ |
|
for (i = 0; i < envs.nr; i++) { |
|
const char *var = envs.items[i].string; |
|
const char *val = envs.items[i].util; |
|
|
|
if (val || !getenv(var)) |
|
continue; |
|
|
|
if (!printed_unset) { |
|
strbuf_addstr(dst, " unset"); |
|
printed_unset = 1; |
|
} |
|
strbuf_addf(dst, " %s", var); |
|
} |
|
if (printed_unset) |
|
strbuf_addch(dst, ';'); |
|
|
|
/* ... followed by "A=B C=D ..." */ |
|
for (i = 0; i < envs.nr; i++) { |
|
const char *var = envs.items[i].string; |
|
const char *val = envs.items[i].util; |
|
const char *oldval; |
|
|
|
if (!val) |
|
continue; |
|
|
|
oldval = getenv(var); |
|
if (oldval && !strcmp(val, oldval)) |
|
continue; |
|
|
|
strbuf_addf(dst, " %s=", var); |
|
sq_quote_buf_pretty(dst, val); |
|
} |
|
string_list_clear(&envs, 0); |
|
} |
|
|
|
static void trace_run_command(const struct child_process *cp) |
|
{ |
|
struct strbuf buf = STRBUF_INIT; |
|
|
|
if (!trace_want(&trace_default_key)) |
|
return; |
|
|
|
strbuf_addstr(&buf, "trace: run_command:"); |
|
if (cp->dir) { |
|
strbuf_addstr(&buf, " cd "); |
|
sq_quote_buf_pretty(&buf, cp->dir); |
|
strbuf_addch(&buf, ';'); |
|
} |
|
/* |
|
* The caller is responsible for initializing cp->env from |
|
* cp->env_array if needed. We only check one place. |
|
*/ |
|
if (cp->env) |
|
trace_add_env(&buf, cp->env); |
|
if (cp->git_cmd) |
|
strbuf_addstr(&buf, " git"); |
|
sq_quote_argv_pretty(&buf, cp->argv); |
|
|
|
trace_printf("%s", buf.buf); |
|
strbuf_release(&buf); |
|
} |
|
|
|
int start_command(struct child_process *cmd) |
|
{ |
|
int need_in, need_out, need_err; |
|
int fdin[2], fdout[2], fderr[2]; |
|
int failed_errno; |
|
char *str; |
|
|
|
if (!cmd->argv) |
|
cmd->argv = cmd->args.v; |
|
if (!cmd->env) |
|
cmd->env = cmd->env_array.v; |
|
|
|
/* |
|
* In case of errors we must keep the promise to close FDs |
|
* that have been passed in via ->in and ->out. |
|
*/ |
|
|
|
need_in = !cmd->no_stdin && cmd->in < 0; |
|
if (need_in) { |
|
if (pipe(fdin) < 0) { |
|
failed_errno = errno; |
|
if (cmd->out > 0) |
|
close(cmd->out); |
|
str = "standard input"; |
|
goto fail_pipe; |
|
} |
|
cmd->in = fdin[1]; |
|
} |
|
|
|
need_out = !cmd->no_stdout |
|
&& !cmd->stdout_to_stderr |
|
&& cmd->out < 0; |
|
if (need_out) { |
|
if (pipe(fdout) < 0) { |
|
failed_errno = errno; |
|
if (need_in) |
|
close_pair(fdin); |
|
else if (cmd->in) |
|
close(cmd->in); |
|
str = "standard output"; |
|
goto fail_pipe; |
|
} |
|
cmd->out = fdout[0]; |
|
} |
|
|
|
need_err = !cmd->no_stderr && cmd->err < 0; |
|
if (need_err) { |
|
if (pipe(fderr) < 0) { |
|
failed_errno = errno; |
|
if (need_in) |
|
close_pair(fdin); |
|
else if (cmd->in) |
|
close(cmd->in); |
|
if (need_out) |
|
close_pair(fdout); |
|
else if (cmd->out) |
|
close(cmd->out); |
|
str = "standard error"; |
|
fail_pipe: |
|
error("cannot create %s pipe for %s: %s", |
|
str, cmd->argv[0], strerror(failed_errno)); |
|
child_process_clear(cmd); |
|
errno = failed_errno; |
|
return -1; |
|
} |
|
cmd->err = fderr[0]; |
|
} |
|
|
|
trace2_child_start(cmd); |
|
trace_run_command(cmd); |
|
|
|
fflush(NULL); |
|
|
|
#ifndef GIT_WINDOWS_NATIVE |
|
{ |
|
int notify_pipe[2]; |
|
int null_fd = -1; |
|
char **childenv; |
|
struct strvec argv = STRVEC_INIT; |
|
struct child_err cerr; |
|
struct atfork_state as; |
|
|
|
if (prepare_cmd(&argv, cmd) < 0) { |
|
failed_errno = errno; |
|
cmd->pid = -1; |
|
if (!cmd->silent_exec_failure) |
|
error_errno("cannot run %s", cmd->argv[0]); |
|
goto end_of_spawn; |
|
} |
|
|
|
if (pipe(notify_pipe)) |
|
notify_pipe[0] = notify_pipe[1] = -1; |
|
|
|
if (cmd->no_stdin || cmd->no_stdout || cmd->no_stderr) { |
|
null_fd = open("/dev/null", O_RDWR | O_CLOEXEC); |
|
if (null_fd < 0) |
|
die_errno(_("open /dev/null failed")); |
|
set_cloexec(null_fd); |
|
} |
|
|
|
childenv = prep_childenv(cmd->env); |
|
atfork_prepare(&as); |
|
|
|
/* |
|
* NOTE: In order to prevent deadlocking when using threads special |
|
* care should be taken with the function calls made in between the |
|
* fork() and exec() calls. No calls should be made to functions which |
|
* require acquiring a lock (e.g. malloc) as the lock could have been |
|
* held by another thread at the time of forking, causing the lock to |
|
* never be released in the child process. This means only |
|
* Async-Signal-Safe functions are permitted in the child. |
|
*/ |
|
cmd->pid = fork(); |
|
failed_errno = errno; |
|
if (!cmd->pid) { |
|
int sig; |
|
/* |
|
* Ensure the default die/error/warn routines do not get |
|
* called, they can take stdio locks and malloc. |
|
*/ |
|
set_die_routine(child_die_fn); |
|
set_error_routine(child_error_fn); |
|
set_warn_routine(child_warn_fn); |
|
|
|
close(notify_pipe[0]); |
|
set_cloexec(notify_pipe[1]); |
|
child_notifier = notify_pipe[1]; |
|
|
|
if (cmd->no_stdin) |
|
child_dup2(null_fd, 0); |
|
else if (need_in) { |
|
child_dup2(fdin[0], 0); |
|
child_close_pair(fdin); |
|
} else if (cmd->in) { |
|
child_dup2(cmd->in, 0); |
|
child_close(cmd->in); |
|
} |
|
|
|
if (cmd->no_stderr) |
|
child_dup2(null_fd, 2); |
|
else if (need_err) { |
|
child_dup2(fderr[1], 2); |
|
child_close_pair(fderr); |
|
} else if (cmd->err > 1) { |
|
child_dup2(cmd->err, 2); |
|
child_close(cmd->err); |
|
} |
|
|
|
if (cmd->no_stdout) |
|
child_dup2(null_fd, 1); |
|
else if (cmd->stdout_to_stderr) |
|
child_dup2(2, 1); |
|
else if (need_out) { |
|
child_dup2(fdout[1], 1); |
|
child_close_pair(fdout); |
|
} else if (cmd->out > 1) { |
|
child_dup2(cmd->out, 1); |
|
child_close(cmd->out); |
|
} |
|
|
|
if (cmd->dir && chdir(cmd->dir)) |
|
child_die(CHILD_ERR_CHDIR); |
|
|
|
/* |
|
* restore default signal handlers here, in case |
|
* we catch a signal right before execve below |
|
*/ |
|
for (sig = 1; sig < NSIG; sig++) { |
|
/* ignored signals get reset to SIG_DFL on execve */ |
|
if (signal(sig, SIG_DFL) == SIG_IGN) |
|
signal(sig, SIG_IGN); |
|
} |
|
|
|
if (sigprocmask(SIG_SETMASK, &as.old, NULL) != 0) |
|
child_die(CHILD_ERR_SIGPROCMASK); |
|
|
|
/* |
|
* Attempt to exec using the command and arguments starting at |
|
* argv.argv[1]. argv.argv[0] contains SHELL_PATH which will |
|
* be used in the event exec failed with ENOEXEC at which point |
|
* we will try to interpret the command using 'sh'. |
|
*/ |
|
execve(argv.v[1], (char *const *) argv.v + 1, |
|
(char *const *) childenv); |
|
if (errno == ENOEXEC) |
|
execve(argv.v[0], (char *const *) argv.v, |
|
(char *const *) childenv); |
|
|
|
if (errno == ENOENT) { |
|
if (cmd->silent_exec_failure) |
|
child_die(CHILD_ERR_SILENT); |
|
child_die(CHILD_ERR_ENOENT); |
|
} else { |
|
child_die(CHILD_ERR_ERRNO); |
|
} |
|
} |
|
atfork_parent(&as); |
|
if (cmd->pid < 0) |
|
error_errno("cannot fork() for %s", cmd->argv[0]); |
|
else if (cmd->clean_on_exit) |
|
mark_child_for_cleanup(cmd->pid, cmd); |
|
|
|
/* |
|
* Wait for child's exec. If the exec succeeds (or if fork() |
|
* failed), EOF is seen immediately by the parent. Otherwise, the |
|
* child process sends a child_err struct. |
|
* Note that use of this infrastructure is completely advisory, |
|
* therefore, we keep error checks minimal. |
|
*/ |
|
close(notify_pipe[1]); |
|
if (xread(notify_pipe[0], &cerr, sizeof(cerr)) == sizeof(cerr)) { |
|
/* |
|
* At this point we know that fork() succeeded, but exec() |
|
* failed. Errors have been reported to our stderr. |
|
*/ |
|
wait_or_whine(cmd->pid, cmd->argv[0], 0); |
|
child_err_spew(cmd, &cerr); |
|
failed_errno = errno; |
|
cmd->pid = -1; |
|
} |
|
close(notify_pipe[0]); |
|
|
|
if (null_fd >= 0) |
|
close(null_fd); |
|
strvec_clear(&argv); |
|
free(childenv); |
|
} |
|
end_of_spawn: |
|
|
|
#else |
|
{ |
|
int fhin = 0, fhout = 1, fherr = 2; |
|
const char **sargv = cmd->argv; |
|
struct strvec nargv = STRVEC_INIT; |
|
|
|
if (cmd->no_stdin) |
|
fhin = open("/dev/null", O_RDWR); |
|
else if (need_in) |
|
fhin = dup(fdin[0]); |
|
else if (cmd->in) |
|
fhin = dup(cmd->in); |
|
|
|
if (cmd->no_stderr) |
|
fherr = open("/dev/null", O_RDWR); |
|
else if (need_err) |
|
fherr = dup(fderr[1]); |
|
else if (cmd->err > 2) |
|
fherr = dup(cmd->err); |
|
|
|
if (cmd->no_stdout) |
|
fhout = open("/dev/null", O_RDWR); |
|
else if (cmd->stdout_to_stderr) |
|
fhout = dup(fherr); |
|
else if (need_out) |
|
fhout = dup(fdout[1]); |
|
else if (cmd->out > 1) |
|
fhout = dup(cmd->out); |
|
|
|
if (cmd->git_cmd) |
|
cmd->argv = prepare_git_cmd(&nargv, cmd->argv); |
|
else if (cmd->use_shell) |
|
cmd->argv = prepare_shell_cmd(&nargv, cmd->argv); |
|
|
|
cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, (char**) cmd->env, |
|
cmd->dir, fhin, fhout, fherr); |
|
failed_errno = errno; |
|
if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT)) |
|
error_errno("cannot spawn %s", cmd->argv[0]); |
|
if (cmd->clean_on_exit && cmd->pid >= 0) |
|
mark_child_for_cleanup(cmd->pid, cmd); |
|
|
|
strvec_clear(&nargv); |
|
cmd->argv = sargv; |
|
if (fhin != 0) |
|
close(fhin); |
|
if (fhout != 1) |
|
close(fhout); |
|
if (fherr != 2) |
|
close(fherr); |
|
} |
|
#endif |
|
|
|
if (cmd->pid < 0) { |
|
trace2_child_exit(cmd, -1); |
|
|
|
if (need_in) |
|
close_pair(fdin); |
|
else if (cmd->in) |
|
close(cmd->in); |
|
if (need_out) |
|
close_pair(fdout); |
|
else if (cmd->out) |
|
close(cmd->out); |
|
if (need_err) |
|
close_pair(fderr); |
|
else if (cmd->err) |
|
close(cmd->err); |
|
child_process_clear(cmd); |
|
errno = failed_errno; |
|
return -1; |
|
} |
|
|
|
if (need_in) |
|
close(fdin[0]); |
|
else if (cmd->in) |
|
close(cmd->in); |
|
|
|
if (need_out) |
|
close(fdout[1]); |
|
else if (cmd->out) |
|
close(cmd->out); |
|
|
|
if (need_err) |
|
close(fderr[1]); |
|
else if (cmd->err) |
|
close(cmd->err); |
|
|
|
return 0; |
|
} |
|
|
|
int finish_command(struct child_process *cmd) |
|
{ |
|
int ret = wait_or_whine(cmd->pid, cmd->argv[0], 0); |
|
trace2_child_exit(cmd, ret); |
|
child_process_clear(cmd); |
|
invalidate_lstat_cache(); |
|
return ret; |
|
} |
|
|
|
int finish_command_in_signal(struct child_process *cmd) |
|
{ |
|
int ret = wait_or_whine(cmd->pid, cmd->argv[0], 1); |
|
trace2_child_exit(cmd, ret); |
|
return ret; |
|
} |
|
|
|
|
|
int run_command(struct child_process *cmd) |
|
{ |
|
int code; |
|
|
|
if (cmd->out < 0 || cmd->err < 0) |
|
BUG("run_command with a pipe can cause deadlock"); |
|
|
|
code = start_command(cmd); |
|
if (code) |
|
return code; |
|
return finish_command(cmd); |
|
} |
|
|
|
int run_command_v_opt(const char **argv, int opt) |
|
{ |
|
return run_command_v_opt_cd_env(argv, opt, NULL, NULL); |
|
} |
|
|
|
int run_command_v_opt_tr2(const char **argv, int opt, const char *tr2_class) |
|
{ |
|
return run_command_v_opt_cd_env_tr2(argv, opt, NULL, NULL, tr2_class); |
|
} |
|
|
|
int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env) |
|
{ |
|
return run_command_v_opt_cd_env_tr2(argv, opt, dir, env, NULL); |
|
} |
|
|
|
int run_command_v_opt_cd_env_tr2(const char **argv, int opt, const char *dir, |
|
const char *const *env, const char *tr2_class) |
|
{ |
|
struct child_process cmd = CHILD_PROCESS_INIT; |
|
cmd.argv = argv; |
|
cmd.no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0; |
|
cmd.git_cmd = opt & RUN_GIT_CMD ? 1 : 0; |
|
cmd.stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0; |
|
cmd.silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0; |
|
cmd.use_shell = opt & RUN_USING_SHELL ? 1 : 0; |
|
cmd.clean_on_exit = opt & RUN_CLEAN_ON_EXIT ? 1 : 0; |
|
cmd.wait_after_clean = opt & RUN_WAIT_AFTER_CLEAN ? 1 : 0; |
|
cmd.dir = dir; |
|
cmd.env = env; |
|
cmd.trace2_child_class = tr2_class; |
|
return run_command(&cmd); |
|
} |
|
|
|
#ifndef NO_PTHREADS |
|
static pthread_t main_thread; |
|
static int main_thread_set; |
|
static pthread_key_t async_key; |
|
static pthread_key_t async_die_counter; |
|
|
|
static void *run_thread(void *data) |
|
{ |
|
struct async *async = data; |
|
intptr_t ret; |
|
|
|
if (async->isolate_sigpipe) { |
|
sigset_t mask; |
|
sigemptyset(&mask); |
|
sigaddset(&mask, SIGPIPE); |
|
if (pthread_sigmask(SIG_BLOCK, &mask, NULL) < 0) { |
|
ret = error("unable to block SIGPIPE in async thread"); |
|
return (void *)ret; |
|
} |
|
} |
|
|
|
pthread_setspecific(async_key, async); |
|
ret = async->proc(async->proc_in, async->proc_out, async->data); |
|
return (void *)ret; |
|
} |
|
|
|
static NORETURN void die_async(const char *err, va_list params) |
|
{ |
|
vreportf("fatal: ", err, params); |
|
|
|
if (in_async()) { |
|
struct async *async = pthread_getspecific(async_key); |
|
if (async->proc_in >= 0) |
|
close(async->proc_in); |
|
if (async->proc_out >= 0) |
|
close(async->proc_out); |
|
pthread_exit((void *)128); |
|
} |
|
|
|
exit(128); |
|
} |
|
|
|
static int async_die_is_recursing(void) |
|
{ |
|
void *ret = pthread_getspecific(async_die_counter); |
|
pthread_setspecific(async_die_counter, (void *)1); |
|
return ret != NULL; |
|
} |
|
|
|
int in_async(void) |
|
{ |
|
if (!main_thread_set) |
|
return 0; /* no asyncs started yet */ |
|
return !pthread_equal(main_thread, pthread_self()); |
|
} |
|
|
|
static void NORETURN async_exit(int code) |
|
{ |
|
pthread_exit((void *)(intptr_t)code); |
|
} |
|
|
|
#else |
|
|
|
static struct { |
|
void (**handlers)(void); |
|
size_t nr; |
|
size_t alloc; |
|
} git_atexit_hdlrs; |
|
|
|
static int git_atexit_installed; |
|
|
|
static void git_atexit_dispatch(void) |
|
{ |
|
size_t i; |
|
|
|
for (i=git_atexit_hdlrs.nr ; i ; i--) |
|
git_atexit_hdlrs.handlers[i-1](); |
|
} |
|
|
|
static void git_atexit_clear(void) |
|
{ |
|
free(git_atexit_hdlrs.handlers); |
|
memset(&git_atexit_hdlrs, 0, sizeof(git_atexit_hdlrs)); |
|
git_atexit_installed = 0; |
|
} |
|
|
|
#undef atexit |
|
int git_atexit(void (*handler)(void)) |
|
{ |
|
ALLOC_GROW(git_atexit_hdlrs.handlers, git_atexit_hdlrs.nr + 1, git_atexit_hdlrs.alloc); |
|
git_atexit_hdlrs.handlers[git_atexit_hdlrs.nr++] = handler; |
|
if (!git_atexit_installed) { |
|
if (atexit(&git_atexit_dispatch)) |
|
return -1; |
|
git_atexit_installed = 1; |
|
} |
|
return 0; |
|
} |
|
#define atexit git_atexit |
|
|
|
static int process_is_async; |
|
int in_async(void) |
|
{ |
|
return process_is_async; |
|
} |
|
|
|
static void NORETURN async_exit(int code) |
|
{ |
|
exit(code); |
|
} |
|
|
|
#endif |
|
|
|
void check_pipe(int err) |
|
{ |
|
if (err == EPIPE) { |
|
if (in_async()) |
|
async_exit(141); |
|
|
|
signal(SIGPIPE, SIG_DFL); |
|
raise(SIGPIPE); |
|
/* Should never happen, but just in case... */ |
|
exit(141); |
|
} |
|
} |
|
|
|
int start_async(struct async *async) |
|
{ |
|
int need_in, need_out; |
|
int fdin[2], fdout[2]; |
|
int proc_in, proc_out; |
|
|
|
need_in = async->in < 0; |
|
if (need_in) { |
|
if (pipe(fdin) < 0) { |
|
if (async->out > 0) |
|
close(async->out); |
|
return error_errno("cannot create pipe"); |
|
} |
|
async->in = fdin[1]; |
|
} |
|
|
|
need_out = async->out < 0; |
|
if (need_out) { |
|
if (pipe(fdout) < 0) { |
|
if (need_in) |
|
close_pair(fdin); |
|
else if (async->in) |
|
close(async->in); |
|
return error_errno("cannot create pipe"); |
|
} |
|
async->out = fdout[0]; |
|
} |
|
|
|
if (need_in) |
|
proc_in = fdin[0]; |
|
else if (async->in) |
|
proc_in = async->in; |
|
else |
|
proc_in = -1; |
|
|
|
if (need_out) |
|
proc_out = fdout[1]; |
|
else if (async->out) |
|
proc_out = async->out; |
|
else |
|
proc_out = -1; |
|
|
|
#ifdef NO_PTHREADS |
|
/* Flush stdio before fork() to avoid cloning buffers */ |
|
fflush(NULL); |
|
|
|
async->pid = fork(); |
|
if (async->pid < 0) { |
|
error_errno("fork (async) failed"); |
|
goto error; |
|
} |
|
if (!async->pid) { |
|
if (need_in) |
|
close(fdin[1]); |
|
if (need_out) |
|
close(fdout[0]); |
|
git_atexit_clear(); |
|
process_is_async = 1; |
|
exit(!!async->proc(proc_in, proc_out, async->data)); |
|
} |
|
|
|
mark_child_for_cleanup(async->pid, NULL); |
|
|
|
if (need_in) |
|
close(fdin[0]); |
|
else if (async->in) |
|
close(async->in); |
|
|
|
if (need_out) |
|
close(fdout[1]); |
|
else if (async->out) |
|
close(async->out); |
|
#else |
|
if (!main_thread_set) { |
|
/* |
|
* We assume that the first time that start_async is called |
|
* it is from the main thread. |
|
*/ |
|
main_thread_set = 1; |
|
main_thread = pthread_self(); |
|
pthread_key_create(&async_key, NULL); |
|
pthread_key_create(&async_die_counter, NULL); |
|
set_die_routine(die_async); |
|
set_die_is_recursing_routine(async_die_is_recursing); |
|
} |
|
|
|
if (proc_in >= 0) |
|
set_cloexec(proc_in); |
|
if (proc_out >= 0) |
|
set_cloexec(proc_out); |
|
async->proc_in = proc_in; |
|
async->proc_out = proc_out; |
|
{ |
|
int err = pthread_create(&async->tid, NULL, run_thread, async); |
|
if (err) { |
|
error(_("cannot create async thread: %s"), strerror(err)); |
|
goto error; |
|
} |
|
} |
|
#endif |
|
return 0; |
|
|
|
error: |
|
if (need_in) |
|
close_pair(fdin); |
|
else if (async->in) |
|
close(async->in); |
|
|
|
if (need_out) |
|
close_pair(fdout); |
|
else if (async->out) |
|
close(async->out); |
|
return -1; |
|
} |
|
|
|
int finish_async(struct async *async) |
|
{ |
|
#ifdef NO_PTHREADS |
|
int ret = wait_or_whine(async->pid, "child process", 0); |
|
|
|
invalidate_lstat_cache(); |
|
|
|
return ret; |
|
#else |
|
void *ret = (void *)(intptr_t)(-1); |
|
|
|
if (pthread_join(async->tid, &ret)) |
|
error("pthread_join failed"); |
|
invalidate_lstat_cache(); |
|
return (int)(intptr_t)ret; |
|
|
|
#endif |
|
} |
|
|
|
int async_with_fork(void) |
|
{ |
|
#ifdef NO_PTHREADS |
|
return 1; |
|
#else |
|
return 0; |
|
#endif |
|
} |
|
|
|
const char *find_hook(const char *name) |
|
{ |
|
static struct strbuf path = STRBUF_INIT; |
|
|
|
strbuf_reset(&path); |
|
strbuf_git_path(&path, "hooks/%s", name); |
|
if (access(path.buf, X_OK) < 0) { |
|
int err = errno; |
|
|
|
#ifdef STRIP_EXTENSION |
|
strbuf_addstr(&path, STRIP_EXTENSION); |
|
if (access(path.buf, X_OK) >= 0) |
|
return path.buf; |
|
if (errno == EACCES) |
|
err = errno; |
|
#endif |
|
|
|
if (err == EACCES && advice_ignored_hook) { |
|
static struct string_list advise_given = STRING_LIST_INIT_DUP; |
|
|
|
if (!string_list_lookup(&advise_given, name)) { |
|
string_list_insert(&advise_given, name); |
|
advise(_("The '%s' hook was ignored because " |
|
"it's not set as executable.\n" |
|
"You can disable this warning with " |
|
"`git config advice.ignoredHook false`."), |
|
path.buf); |
|
} |
|
} |
|
return NULL; |
|
} |
|
return path.buf; |
|
} |
|
|
|
int run_hook_ve(const char *const *env, const char *name, va_list args) |
|
{ |
|
struct child_process hook = CHILD_PROCESS_INIT; |
|
const char *p; |
|
|
|
p = find_hook(name); |
|
if (!p) |
|
return 0; |
|
|
|
strvec_push(&hook.args, p); |
|
while ((p = va_arg(args, const char *))) |
|
strvec_push(&hook.args, p); |
|
hook.env = env; |
|
hook.no_stdin = 1; |
|
hook.stdout_to_stderr = 1; |
|
hook.trace2_hook_name = name; |
|
|
|
return run_command(&hook); |
|
} |
|
|
|
int run_hook_le(const char *const *env, const char *name, ...) |
|
{ |
|
va_list args; |
|
int ret; |
|
|
|
va_start(args, name); |
|
ret = run_hook_ve(env, name, args); |
|
va_end(args); |
|
|
|
return ret; |
|
} |
|
|
|
struct io_pump { |
|
/* initialized by caller */ |
|
int fd; |
|
int type; /* POLLOUT or POLLIN */ |
|
union { |
|
struct { |
|
const char *buf; |
|
size_t len; |
|
} out; |
|
struct { |
|
struct strbuf *buf; |
|
size_t hint; |
|
} in; |
|
} u; |
|
|
|
/* returned by pump_io */ |
|
int error; /* 0 for success, otherwise errno */ |
|
|
|
/* internal use */ |
|
struct pollfd *pfd; |
|
}; |
|
|
|
static int pump_io_round(struct io_pump *slots, int nr, struct pollfd *pfd) |
|
{ |
|
int pollsize = 0; |
|
int i; |
|
|
|
for (i = 0; i < nr; i++) { |
|
struct io_pump *io = &slots[i]; |
|
if (io->fd < 0) |
|
continue; |
|
pfd[pollsize].fd = io->fd; |
|
pfd[pollsize].events = io->type; |
|
io->pfd = &pfd[pollsize++]; |
|
} |
|
|
|
if (!pollsize) |
|
return 0; |
|
|
|
if (poll(pfd, pollsize, -1) < 0) { |
|
if (errno == EINTR) |
|
return 1; |
|
die_errno("poll failed"); |
|
} |
|
|
|
for (i = 0; i < nr; i++) { |
|
struct io_pump *io = &slots[i]; |
|
|
|
if (io->fd < 0) |
|
continue; |
|
|
|
if (!(io->pfd->revents & (POLLOUT|POLLIN|POLLHUP|POLLERR|POLLNVAL))) |
|
continue; |
|
|
|
if (io->type == POLLOUT) { |
|
ssize_t len = xwrite(io->fd, |
|
io->u.out.buf, io->u.out.len); |
|
if (len < 0) { |
|
io->error = errno; |
|
close(io->fd); |
|
io->fd = -1; |
|
} else { |
|
io->u.out.buf += len; |
|
io->u.out.len -= len; |
|
if (!io->u.out.len) { |
|
close(io->fd); |
|
io->fd = -1; |
|
} |
|
} |
|
} |
|
|
|
if (io->type == POLLIN) { |
|
ssize_t len = strbuf_read_once(io->u.in.buf, |
|
io->fd, io->u.in.hint); |
|
if (len < 0) |
|
io->error = errno; |
|
if (len <= 0) { |
|
close(io->fd); |
|
io->fd = -1; |
|
} |
|
} |
|
} |
|
|
|
return 1; |
|
} |
|
|
|
static int pump_io(struct io_pump *slots, int nr) |
|
{ |
|
struct pollfd *pfd; |
|
int i; |
|
|
|
for (i = 0; i < nr; i++) |
|
slots[i].error = 0; |
|
|
|
ALLOC_ARRAY(pfd, nr); |
|
while (pump_io_round(slots, nr, pfd)) |
|
; /* nothing */ |
|
free(pfd); |
|
|
|
/* There may be multiple errno values, so just pick the first. */ |
|
for (i = 0; i < nr; i++) { |
|
if (slots[i].error) { |
|
errno = slots[i].error; |
|
return -1; |
|
} |
|
} |
|
return 0; |
|
} |
|
|
|
|
|
int pipe_command(struct child_process *cmd, |
|
const char *in, size_t in_len, |
|
struct strbuf *out, size_t out_hint, |
|
struct strbuf *err, size_t err_hint) |
|
{ |
|
struct io_pump io[3]; |
|
int nr = 0; |
|
|
|
if (in) |
|
cmd->in = -1; |
|
if (out) |
|
cmd->out = -1; |
|
if (err) |
|
cmd->err = -1; |
|
|
|
if (start_command(cmd) < 0) |
|
return -1; |
|
|
|
if (in) { |
|
io[nr].fd = cmd->in; |
|
io[nr].type = POLLOUT; |
|
io[nr].u.out.buf = in; |
|
io[nr].u.out.len = in_len; |
|
nr++; |
|
} |
|
if (out) { |
|
io[nr].fd = cmd->out; |
|
io[nr].type = POLLIN; |
|
io[nr].u.in.buf = out; |
|
io[nr].u.in.hint = out_hint; |
|
nr++; |
|
} |
|
if (err) { |
|
io[nr].fd = cmd->err; |
|
io[nr].type = POLLIN; |
|
io[nr].u.in.buf = err; |
|
io[nr].u.in.hint = err_hint; |
|
nr++; |
|
} |
|
|
|
if (pump_io(io, nr) < 0) { |
|
finish_command(cmd); /* throw away exit code */ |
|
return -1; |
|
} |
|
|
|
return finish_command(cmd); |
|
} |
|
|
|
enum child_state { |
|
GIT_CP_FREE, |
|
GIT_CP_WORKING, |
|
GIT_CP_WAIT_CLEANUP, |
|
}; |
|
|
|
struct parallel_processes { |
|
void *data; |
|
|
|
int max_processes; |
|
int nr_processes; |
|
|
|
get_next_task_fn get_next_task; |
|
start_failure_fn start_failure; |
|
task_finished_fn task_finished; |
|
|
|
struct { |
|
enum child_state state; |
|
struct child_process process; |
|
struct strbuf err; |
|
void *data; |
|
} *children; |
|
/* |
|
* The struct pollfd is logically part of *children, |
|
* but the system call expects it as its own array. |
|
*/ |
|
struct pollfd *pfd; |
|
|
|
unsigned shutdown : 1; |
|
|
|
int output_owner; |
|
struct strbuf buffered_output; /* of finished children */ |
|
}; |
|
|
|
static int default_start_failure(struct strbuf *out, |
|
void *pp_cb, |
|
void *pp_task_cb) |
|
{ |
|
return 0; |
|
} |
|
|
|
static int default_task_finished(int result, |
|
struct strbuf *out, |
|
void *pp_cb, |
|
void *pp_task_cb) |
|
{ |
|
return 0; |
|
} |
|
|
|
static void kill_children(struct parallel_processes *pp, int signo) |
|
{ |
|
int i, n = pp->max_processes; |
|
|
|
for (i = 0; i < n; i++) |
|
if (pp->children[i].state == GIT_CP_WORKING) |
|
kill(pp->children[i].process.pid, signo); |
|
} |
|
|
|
static struct parallel_processes *pp_for_signal; |
|
|
|
static void handle_children_on_signal(int signo) |
|
{ |
|
kill_children(pp_for_signal, signo); |
|
sigchain_pop(signo); |
|
raise(signo); |
|
} |
|
|
|
static void pp_init(struct parallel_processes *pp, |
|
int n, |
|
get_next_task_fn get_next_task, |
|
start_failure_fn start_failure, |
|
task_finished_fn task_finished, |
|
void *data) |
|
{ |
|
int i; |
|
|
|
if (n < 1) |
|
n = online_cpus(); |
|
|
|
pp->max_processes = n; |
|
|
|
trace_printf("run_processes_parallel: preparing to run up to %d tasks", n); |
|
|
|
pp->data = data; |
|
if (!get_next_task) |
|
BUG("you need to specify a get_next_task function"); |
|
pp->get_next_task = get_next_task; |
|
|
|
pp->start_failure = start_failure ? start_failure : default_start_failure; |
|
pp->task_finished = task_finished ? task_finished : default_task_finished; |
|
|
|
pp->nr_processes = 0; |
|
pp->output_owner = 0; |
|
pp->shutdown = 0; |
|
CALLOC_ARRAY(pp->children, n); |
|
CALLOC_ARRAY(pp->pfd, n); |
|
strbuf_init(&pp->buffered_output, 0); |
|
|
|
for (i = 0; i < n; i++) { |
|
strbuf_init(&pp->children[i].err, 0); |
|
child_process_init(&pp->children[i].process); |
|
pp->pfd[i].events = POLLIN | POLLHUP; |
|
pp->pfd[i].fd = -1; |
|
} |
|
|
|
pp_for_signal = pp; |
|
sigchain_push_common(handle_children_on_signal); |
|
} |
|
|
|
static void pp_cleanup(struct parallel_processes *pp) |
|
{ |
|
int i; |
|
|
|
trace_printf("run_processes_parallel: done"); |
|
for (i = 0; i < pp->max_processes; i++) { |
|
strbuf_release(&pp->children[i].err); |
|
child_process_clear(&pp->children[i].process); |
|
} |
|
|
|
free(pp->children); |
|
free(pp->pfd); |
|
|
|
/* |
|
* When get_next_task added messages to the buffer in its last |
|
* iteration, the buffered output is non empty. |
|
*/ |
|
strbuf_write(&pp->buffered_output, stderr); |
|
strbuf_release(&pp->buffered_output); |
|
|
|
sigchain_pop_common(); |
|
} |
|
|
|
/* returns |
|
* 0 if a new task was started. |
|
* 1 if no new jobs was started (get_next_task ran out of work, non critical |
|
* problem with starting a new command) |
|
* <0 no new job was started, user wishes to shutdown early. Use negative code |
|
* to signal the children. |
|
*/ |
|
static int pp_start_one(struct parallel_processes *pp) |
|
{ |
|
int i, code; |
|
|
|
for (i = 0; i < pp->max_processes; i++) |
|
if (pp->children[i].state == GIT_CP_FREE) |
|
break; |
|
if (i == pp->max_processes) |
|
BUG("bookkeeping is hard"); |
|
|
|
code = pp->get_next_task(&pp->children[i].process, |
|
&pp->children[i].err, |
|
pp->data, |
|
&pp->children[i].data); |
|
if (!code) { |
|
strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
|
strbuf_reset(&pp->children[i].err); |
|
return 1; |
|
} |
|
pp->children[i].process.err = -1; |
|
pp->children[i].process.stdout_to_stderr = 1; |
|
pp->children[i].process.no_stdin = 1; |
|
|
|
if (start_command(&pp->children[i].process)) { |
|
code = pp->start_failure(&pp->children[i].err, |
|
pp->data, |
|
pp->children[i].data); |
|
strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
|
strbuf_reset(&pp->children[i].err); |
|
if (code) |
|
pp->shutdown = 1; |
|
return code; |
|
} |
|
|
|
pp->nr_processes++; |
|
pp->children[i].state = GIT_CP_WORKING; |
|
pp->pfd[i].fd = pp->children[i].process.err; |
|
return 0; |
|
} |
|
|
|
static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout) |
|
{ |
|
int i; |
|
|
|
while ((i = poll(pp->pfd, pp->max_processes, output_timeout)) < 0) { |
|
if (errno == EINTR) |
|
continue; |
|
pp_cleanup(pp); |
|
die_errno("poll"); |
|
} |
|
|
|
/* Buffer output from all pipes. */ |
|
for (i = 0; i < pp->max_processes; i++) { |
|
if (pp->children[i].state == GIT_CP_WORKING && |
|
pp->pfd[i].revents & (POLLIN | POLLHUP)) { |
|
int n = strbuf_read_once(&pp->children[i].err, |
|
pp->children[i].process.err, 0); |
|
if (n == 0) { |
|
close(pp->children[i].process.err); |
|
pp->children[i].state = GIT_CP_WAIT_CLEANUP; |
|
} else if (n < 0) |
|
if (errno != EAGAIN) |
|
die_errno("read"); |
|
} |
|
} |
|
} |
|
|
|
static void pp_output(struct parallel_processes *pp) |
|
{ |
|
int i = pp->output_owner; |
|
if (pp->children[i].state == GIT_CP_WORKING && |
|
pp->children[i].err.len) { |
|
strbuf_write(&pp->children[i].err, stderr); |
|
strbuf_reset(&pp->children[i].err); |
|
} |
|
} |
|
|
|
static int pp_collect_finished(struct parallel_processes *pp) |
|
{ |
|
int i, code; |
|
int n = pp->max_processes; |
|
int result = 0; |
|
|
|
while (pp->nr_processes > 0) { |
|
for (i = 0; i < pp->max_processes; i++) |
|
if (pp->children[i].state == GIT_CP_WAIT_CLEANUP) |
|
break; |
|
if (i == pp->max_processes) |
|
break; |
|
|
|
code = finish_command(&pp->children[i].process); |
|
|
|
code = pp->task_finished(code, |
|
&pp->children[i].err, pp->data, |
|
pp->children[i].data); |
|
|
|
if (code) |
|
result = code; |
|
if (code < 0) |
|
break; |
|
|
|
pp->nr_processes--; |
|
pp->children[i].state = GIT_CP_FREE; |
|
pp->pfd[i].fd = -1; |
|
child_process_init(&pp->children[i].process); |
|
|
|
if (i != pp->output_owner) { |
|
strbuf_addbuf(&pp->buffered_output, &pp->children[i].err); |
|
strbuf_reset(&pp->children[i].err); |
|
} else { |
|
strbuf_write(&pp->children[i].err, stderr); |
|
strbuf_reset(&pp->children[i].err); |
|
|
|
/* Output all other finished child processes */ |
|
strbuf_write(&pp->buffered_output, stderr); |
|
strbuf_reset(&pp->buffered_output); |
|
|
|
/* |
|
* Pick next process to output live. |
|
* NEEDSWORK: |
|
* For now we pick it randomly by doing a round |
|
* robin. Later we may want to pick the one with |
|
* the most output or the longest or shortest |
|
* running process time. |
|
*/ |
|
for (i = 0; i < n; i++) |
|
if (pp->children[(pp->output_owner + i) % n].state == GIT_CP_WORKING) |
|
break; |
|
pp->output_owner = (pp->output_owner + i) % n; |
|
} |
|
} |
|
return result; |
|
} |
|
|
|
int run_processes_parallel(int n, |
|
get_next_task_fn get_next_task, |
|
start_failure_fn start_failure, |
|
task_finished_fn task_finished, |
|
void *pp_cb) |
|
{ |
|
int i, code; |
|
int output_timeout = 100; |
|
int spawn_cap = 4; |
|
struct parallel_processes pp; |
|
|
|
pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb); |
|
while (1) { |
|
for (i = 0; |
|
i < spawn_cap && !pp.shutdown && |
|
pp.nr_processes < pp.max_processes; |
|
i++) { |
|
code = pp_start_one(&pp); |
|
if (!code) |
|
continue; |
|
if (code < 0) { |
|
pp.shutdown = 1; |
|
kill_children(&pp, -code); |
|
} |
|
break; |
|
} |
|
if (!pp.nr_processes) |
|
break; |
|
pp_buffer_stderr(&pp, output_timeout); |
|
pp_output(&pp); |
|
code = pp_collect_finished(&pp); |
|
if (code) { |
|
pp.shutdown = 1; |
|
if (code < 0) |
|
kill_children(&pp, -code); |
|
} |
|
} |
|
|
|
pp_cleanup(&pp); |
|
return 0; |
|
} |
|
|
|
int run_processes_parallel_tr2(int n, get_next_task_fn get_next_task, |
|
start_failure_fn start_failure, |
|
task_finished_fn task_finished, void *pp_cb, |
|
const char *tr2_category, const char *tr2_label) |
|
{ |
|
int result; |
|
|
|
trace2_region_enter_printf(tr2_category, tr2_label, NULL, "max:%d", |
|
((n < 1) ? online_cpus() : n)); |
|
|
|
result = run_processes_parallel(n, get_next_task, start_failure, |
|
task_finished, pp_cb); |
|
|
|
trace2_region_leave(tr2_category, tr2_label, NULL); |
|
|
|
return result; |
|
} |
|
|
|
int run_auto_maintenance(int quiet) |
|
{ |
|
int enabled; |
|
struct child_process maint = CHILD_PROCESS_INIT; |
|
|
|
if (!git_config_get_bool("maintenance.auto", &enabled) && |
|
!enabled) |
|
return 0; |
|
|
|
maint.git_cmd = 1; |
|
strvec_pushl(&maint.args, "maintenance", "run", "--auto", NULL); |
|
strvec_push(&maint.args, quiet ? "--quiet" : "--no-quiet"); |
|
|
|
return run_command(&maint); |
|
}
|
|
|