X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=path.c;h=2c077c0c8f7066c5338050ce890c0846adedf6bd;hb=4275df517022604f5c33ba05ae45a885b84e3472;hp=495d17ca4ca371f4b5bdb6f1f3de9a6a9d84280b;hpb=5da1606d0bf5b970fadfa0ca91618a1e871f6755;p=git.git

diff --git a/path.c b/path.c
index 495d17ca..2c077c0c 100644
--- a/path.c
+++ b/path.c
@@ -11,6 +11,7 @@
  * which is what it's designed for.
  */
 #include "cache.h"
+#include <pwd.h>
 
 static char pathname[PATH_MAX];
 static char bad_path[] = "/bad-path/";
@@ -89,3 +90,118 @@ char *safe_strncpy(char *dest, const char *src, size_t n)
 
 	return dest;
 }
+
+int validate_symref(const char *path)
+{
+	struct stat st;
+	char *buf, buffer[256];
+	int len, fd;
+
+	if (lstat(path, &st) < 0)
+		return -1;
+
+	/* Make sure it is a "refs/.." symlink */
+	if (S_ISLNK(st.st_mode)) {
+		len = readlink(path, buffer, sizeof(buffer)-1);
+		if (len >= 5 && !memcmp("refs/", buffer, 5))
+			return 0;
+		return -1;
+	}
+
+	/*
+	 * Anything else, just open it and try to see if it is a symbolic ref.
+	 */
+	fd = open(path, O_RDONLY);
+	if (fd < 0)
+		return -1;
+	len = read(fd, buffer, sizeof(buffer)-1);
+	close(fd);
+
+	/*
+	 * Is it a symbolic ref?
+	 */
+	if (len < 4 || memcmp("ref:", buffer, 4))
+		return -1;
+	buf = buffer + 4;
+	len -= 4;
+	while (len && isspace(*buf))
+		buf++, len--;
+	if (len >= 5 && !memcmp("refs/", buf, 5))
+		return 0;
+	return -1;
+}
+
+static char *current_dir(void)
+{
+	return getcwd(pathname, sizeof(pathname));
+}
+
+static int user_chdir(char *path)
+{
+	char *dir = path;
+
+	if(*dir == '~') {		/* user-relative path */
+		struct passwd *pw;
+		char *slash = strchr(dir, '/');
+
+		dir++;
+		/* '~/' and '~' (no slash) means users own home-dir */
+		if(!*dir || *dir == '/')
+			pw = getpwuid(getuid());
+		else {
+			if (slash) {
+				*slash = '\0';
+				pw = getpwnam(dir);
+				*slash = '/';
+			}
+			else
+				pw = getpwnam(dir);
+		}
+
+		/* make sure we got something back that we can chdir() to */
+		if(!pw || chdir(pw->pw_dir) < 0)
+			return -1;
+
+		if(!slash || !slash[1]) /* no path following username */
+			return 0;
+
+		dir = slash + 1;
+	}
+
+	/* ~foo/path/to/repo is now path/to/repo and we're in foo's homedir */
+	if(chdir(dir) < 0)
+		return -1;
+
+	return 0;
+}
+
+char *enter_repo(char *path, int strict)
+{
+	if(!path)
+		return NULL;
+
+	if (strict) {
+		if (chdir(path) < 0)
+			return NULL;
+	}
+	else {
+		if (!*path)
+			; /* happy -- no chdir */
+		else if (!user_chdir(path))
+			; /* happy -- as given */
+		else if (!user_chdir(mkpath("%s.git", path)))
+			; /* happy -- uemacs --> uemacs.git */
+		else
+			return NULL;
+		(void)chdir(".git");
+	}
+
+	if(access("objects", X_OK) == 0 && access("refs", X_OK) == 0 &&
+	   validate_symref("HEAD") == 0) {
+		putenv("GIT_DIR=.");
+		check_repository_format();
+		return current_dir();
+	}
+
+	return NULL;
+}