git-remote-ext
[gitweb.git] / path.c
diff --git a/path.c b/path.c
index 00d06332959af03b036b3d0b5ad115dd3b46b920..a2c9d1e24afb9d1250c846791607c49d82e9565e 100644 (file)
--- a/path.c
+++ b/path.c
@@ -122,6 +122,44 @@ char *git_path(const char *fmt, ...)
        return cleanup_path(pathname);
 }
 
+char *git_path_submodule(const char *path, const char *fmt, ...)
+{
+       char *pathname = get_pathname();
+       struct strbuf buf = STRBUF_INIT;
+       const char *git_dir;
+       va_list args;
+       unsigned len;
+
+       len = strlen(path);
+       if (len > PATH_MAX-100)
+               return bad_path;
+
+       strbuf_addstr(&buf, path);
+       if (len && path[len-1] != '/')
+               strbuf_addch(&buf, '/');
+       strbuf_addstr(&buf, ".git");
+
+       git_dir = read_gitfile_gently(buf.buf);
+       if (git_dir) {
+               strbuf_reset(&buf);
+               strbuf_addstr(&buf, git_dir);
+       }
+       strbuf_addch(&buf, '/');
+
+       if (buf.len >= PATH_MAX)
+               return bad_path;
+       memcpy(pathname, buf.buf, buf.len + 1);
+
+       strbuf_release(&buf);
+       len = strlen(pathname);
+
+       va_start(args, fmt);
+       len += vsnprintf(pathname + len, PATH_MAX - len, fmt, args);
+       va_end(args);
+       if (len >= PATH_MAX)
+               return bad_path;
+       return cleanup_path(pathname);
+}
 
 /* git_mkstemp() - create tmp file honoring TMPDIR variable */
 int git_mkstemp(char *path, size_t len, const char *template)
@@ -157,6 +195,85 @@ int git_mkstemps(char *path, size_t len, const char *template, int suffix_len)
        return mkstemps(path, suffix_len);
 }
 
+/* Adapted from libiberty's mkstemp.c. */
+
+#undef TMP_MAX
+#define TMP_MAX 16384
+
+int git_mkstemps_mode(char *pattern, int suffix_len, int mode)
+{
+       static const char letters[] =
+               "abcdefghijklmnopqrstuvwxyz"
+               "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+               "0123456789";
+       static const int num_letters = 62;
+       uint64_t value;
+       struct timeval tv;
+       char *template;
+       size_t len;
+       int fd, count;
+
+       len = strlen(pattern);
+
+       if (len < 6 + suffix_len) {
+               errno = EINVAL;
+               return -1;
+       }
+
+       if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) {
+               errno = EINVAL;
+               return -1;
+       }
+
+       /*
+        * Replace pattern's XXXXXX characters with randomness.
+        * Try TMP_MAX different filenames.
+        */
+       gettimeofday(&tv, NULL);
+       value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid();
+       template = &pattern[len - 6 - suffix_len];
+       for (count = 0; count < TMP_MAX; ++count) {
+               uint64_t v = value;
+               /* Fill in the random bits. */
+               template[0] = letters[v % num_letters]; v /= num_letters;
+               template[1] = letters[v % num_letters]; v /= num_letters;
+               template[2] = letters[v % num_letters]; v /= num_letters;
+               template[3] = letters[v % num_letters]; v /= num_letters;
+               template[4] = letters[v % num_letters]; v /= num_letters;
+               template[5] = letters[v % num_letters]; v /= num_letters;
+
+               fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode);
+               if (fd > 0)
+                       return fd;
+               /*
+                * Fatal error (EPERM, ENOSPC etc).
+                * It doesn't make sense to loop.
+                */
+               if (errno != EEXIST)
+                       break;
+               /*
+                * This is a random value.  It is only necessary that
+                * the next TMP_MAX values generated by adding 7777 to
+                * VALUE are different with (module 2^32).
+                */
+               value += 7777;
+       }
+       /* We return the null string if we can't find a unique file name.  */
+       pattern[0] = '\0';
+       return -1;
+}
+
+int git_mkstemp_mode(char *pattern, int mode)
+{
+       /* mkstemp is just mkstemps with no suffix */
+       return git_mkstemps_mode(pattern, 0, mode);
+}
+
+int gitmkstemps(char *pattern, int suffix_len)
+{
+       return git_mkstemps_mode(pattern, suffix_len, 0600);
+}
+
 int validate_headref(const char *path)
 {
        struct stat st;
@@ -237,6 +354,8 @@ char *expand_user_path(const char *path)
                size_t username_len = first_slash - username;
                if (username_len == 0) {
                        const char *home = getenv("HOME");
+                       if (!home)
+                               goto return_null;
                        strbuf_add(&user_path, home, strlen(home));
                } else {
                        struct passwd *pw = getpw_str(username, username_len);
@@ -336,7 +455,7 @@ char *enter_repo(char *path, int strict)
 
        if (access("objects", X_OK) == 0 && access("refs", X_OK) == 0 &&
            validate_headref("HEAD") == 0) {
-               setenv(GIT_DIR_ENVIRONMENT, ".", 1);
+               set_git_dir(".");
                check_repository_format();
                return path;
        }
@@ -394,17 +513,38 @@ int set_shared_perm(const char *path, int mode)
 const char *make_relative_path(const char *abs, const char *base)
 {
        static char buf[PATH_MAX + 1];
-       int baselen;
-       if (!base)
-               return abs;
-       baselen = strlen(base);
-       if (prefixcmp(abs, base))
+       int i = 0, j = 0;
+
+       if (!base || !base[0])
                return abs;
-       if (abs[baselen] == '/')
-               baselen++;
-       else if (base[baselen - 1] != '/')
+       while (base[i]) {
+               if (is_dir_sep(base[i])) {
+                       if (!is_dir_sep(abs[j]))
+                               return abs;
+                       while (is_dir_sep(base[i]))
+                               i++;
+                       while (is_dir_sep(abs[j]))
+                               j++;
+                       continue;
+               } else if (abs[j] != base[i]) {
+                       return abs;
+               }
+               i++;
+               j++;
+       }
+       if (
+           /* "/foo" is a prefix of "/foo" */
+           abs[j] &&
+           /* "/foo" is not a prefix of "/foobar" */
+           !is_dir_sep(base[i-1]) && !is_dir_sep(abs[j])
+          )
                return abs;
-       strcpy(buf, abs + baselen);
+       while (is_dir_sep(abs[j]))
+               j++;
+       if (!abs[j])
+               strcpy(buf, ".");
+       else
+               strcpy(buf, abs + j);
        return buf;
 }
 
@@ -581,3 +721,57 @@ char *strip_path_suffix(const char *path, const char *suffix)
                return NULL;
        return xstrndup(path, chomp_trailing_dir_sep(path, path_len));
 }
+
+int daemon_avoid_alias(const char *p)
+{
+       int sl, ndot;
+
+       /*
+        * This resurrects the belts and suspenders paranoia check by HPA
+        * done in <435560F7.4080006@zytor.com> thread, now enter_repo()
+        * does not do getcwd() based path canonicalization.
+        *
+        * sl becomes true immediately after seeing '/' and continues to
+        * be true as long as dots continue after that without intervening
+        * non-dot character.
+        */
+       if (!p || (*p != '/' && *p != '~'))
+               return -1;
+       sl = 1; ndot = 0;
+       p++;
+
+       while (1) {
+               char ch = *p++;
+               if (sl) {
+                       if (ch == '.')
+                               ndot++;
+                       else if (ch == '/') {
+                               if (ndot < 3)
+                                       /* reject //, /./ and /../ */
+                                       return -1;
+                               ndot = 0;
+                       }
+                       else if (ch == 0) {
+                               if (0 < ndot && ndot < 3)
+                                       /* reject /.$ and /..$ */
+                                       return -1;
+                               return 0;
+                       }
+                       else
+                               sl = ndot = 0;
+               }
+               else if (ch == 0)
+                       return 0;
+               else if (ch == '/') {
+                       sl = 1;
+                       ndot = 0;
+               }
+       }
+}
+
+int offset_1st_component(const char *path)
+{
+       if (has_dos_drive_prefix(path))
+               return 2 + is_dir_sep(path[2]);
+       return is_dir_sep(path[0]);
+}