X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=path.c;h=ab2e3687ab1c58c4a9e87679093208a701a0bfbd;hb=00787ed55adbc2350efa911bf0bdebf6ca08c095;hp=2ec950b27f1c3e4919ce7d1696360c5a49abb724;hpb=32ef08f4e5ab6ce8f3b47201f1df46d1a33deb80;p=git.git

diff --git a/path.c b/path.c
index 2ec950b27..ab2e3687a 100644
--- a/path.c
+++ b/path.c
@@ -157,6 +157,75 @@ 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 gitmkstemps(char *pattern, int suffix_len)
+{
+	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, 0600);
+		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';
+	errno = EINVAL;
+	return -1;
+}
+
 int validate_headref(const char *path)
 {
 	struct stat st;
@@ -394,17 +463,38 @@ 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;
 }