diff --git a/Makefile b/Makefile index ff5fc5fbe2..b593446efb 100644 --- a/Makefile +++ b/Makefile @@ -944,7 +944,7 @@ endif ### Testing rules -TEST_PROGRAMS = test-chmtime$X test-genrandom$X test-date$X test-delta$X test-sha1$X test-match-trees$X +TEST_PROGRAMS = test-chmtime$X test-genrandom$X test-date$X test-delta$X test-sha1$X test-match-trees$X test-absolute-path$X all:: $(TEST_PROGRAMS) diff --git a/cache.h b/cache.h index 53801b8089..98af53040d 100644 --- a/cache.h +++ b/cache.h @@ -358,6 +358,11 @@ int git_config_perm(const char *var, const char *value); int adjust_shared_perm(const char *path); int safe_create_leading_directories(char *path); char *enter_repo(char *path, int strict); +static inline int is_absolute_path(const char *path) +{ + return path[0] == '/'; +} +const char *make_absolute_path(const char *path); /* Read and unpack a sha1 file into memory, write memory to a sha1 file */ extern int sha1_object_info(const unsigned char *, unsigned long *); diff --git a/path.c b/path.c index dfff41f626..42609524a5 100644 --- a/path.c +++ b/path.c @@ -288,3 +288,68 @@ int adjust_shared_perm(const char *path) return -2; return 0; } + +/* We allow "recursive" symbolic links. Only within reason, though. */ +#define MAXDEPTH 5 + +const char *make_absolute_path(const char *path) +{ + static char bufs[2][PATH_MAX + 1], *buf = bufs[0], *next_buf = bufs[1]; + char cwd[1024] = ""; + int buf_index = 1, len; + + int depth = MAXDEPTH; + char *last_elem = NULL; + struct stat st; + + if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX) + die ("Too long path: %.*s", 60, path); + + while (depth--) { + if (stat(buf, &st) || !S_ISDIR(st.st_mode)) { + char *last_slash = strrchr(buf, '/'); + if (last_slash) { + *last_slash = '\0'; + last_elem = xstrdup(last_slash + 1); + } else + last_elem = xstrdup(buf); + } + + if (*buf) { + if (!*cwd && !getcwd(cwd, sizeof(cwd))) + die ("Could not get current working directory"); + + if (chdir(buf)) + die ("Could not switch to '%s'", buf); + } + if (!getcwd(buf, PATH_MAX)) + die ("Could not get current working directory"); + + if (last_elem) { + int len = strlen(buf); + if (len + strlen(last_elem) + 2 > PATH_MAX) + die ("Too long path name: '%s/%s'", + buf, last_elem); + buf[len] = '/'; + strcpy(buf + len + 1, last_elem); + free(last_elem); + last_elem = NULL; + } + + if (!lstat(buf, &st) && S_ISLNK(st.st_mode)) { + len = readlink(buf, next_buf, PATH_MAX); + if (len < 0) + die ("Invalid symlink: %s", buf); + next_buf[len] = '\0'; + buf = next_buf; + buf_index = 1 - buf_index; + next_buf = bufs[buf_index]; + } else + break; + } + + if (*cwd && chdir(cwd)) + die ("Could not change back to '%s'", cwd); + + return buf; +} diff --git a/t/t0000-basic.sh b/t/t0000-basic.sh index 4bba9c0717..4e49d59065 100755 --- a/t/t0000-basic.sh +++ b/t/t0000-basic.sh @@ -281,4 +281,20 @@ test_expect_success 'update-index D/F conflict' ' test $numpath0 = 1 ' +test_expect_success 'absolute path works as expected' ' + mkdir first && + ln -s ../.git first/.git && + mkdir second && + ln -s ../first second/other && + mkdir third && + dir="$(cd .git; pwd -P)" && + dir2=third/../second/other/.git && + test "$dir" = "$(test-absolute-path $dir2)" && + file="$dir"/index && + test "$file" = "$(test-absolute-path $dir2/index)" && + ln -s ../first/file .git/syml && + sym="$(cd first; pwd -P)"/file && + test "$sym" = "$(test-absolute-path $dir2/syml)" +' + test_done diff --git a/test-absolute-path.c b/test-absolute-path.c new file mode 100644 index 0000000000..c959ea20d3 --- /dev/null +++ b/test-absolute-path.c @@ -0,0 +1,11 @@ +#include "cache.h" + +int main(int argc, char **argv) +{ + while (argc > 1) { + puts(make_absolute_path(argv[1])); + argc--; + argv++; + } + return 0; +}