[PATCH] git-tar-tree: add symlink support

Add symlink support to git-tar-tree.

diff --git a/tar-tree.c b/tar-tree.c
index e99adc7..a09cb41 100644 (file)
--- a/tar-tree.c
+++ b/tar-tree.c
@@ -6,10 +6,14 @@
 
 #define TYPEFLAG_AUTO          '\0'
 #define TYPEFLAG_REG           '0'
+#define TYPEFLAG_LNK           '2'
 #define TYPEFLAG_DIR           '5'
 #define TYPEFLAG_GLOBAL_HEADER 'g'
 #define TYPEFLAG_EXT_HEADER    'x'
 
+#define EXT_HEADER_PATH                1
+#define EXT_HEADER_LINKPATH    2
+
 static const char *tar_tree_usage = "tar-tree <key> [basedir]";
 
 static char block[BLOCKSIZE];
@@ -209,9 +213,13 @@ static void write_extended_header(const char *headerfilename, int is_dir,
                                   void *content, unsigned int contentsize)
 {
        char *p;
-       unsigned int pathlen, size;
+       unsigned int pathlen, size, linkpathlen = 0;
 
        size = pathlen = extended_header_len("path", namelen);
+       if (flags & EXT_HEADER_LINKPATH) {
+               linkpathlen = extended_header_len("linkpath", contentsize);
+               size += linkpathlen;
+       }
        if (size > RECORDSIZE)
                die("tar-tree: extended header too big, wtf?");
        write_header(NULL, TYPEFLAG_EXT_HEADER, NULL, NULL, headerfilename,
@@ -221,6 +229,8 @@ static void write_extended_header(const char *headerfilename, int is_dir,
        append_extended_header_prefix(&p, pathlen, "path");
        append_path(&p, is_dir, basepath, prefix, path);
        append_char(&p, '\n');
+       if (flags & EXT_HEADER_LINKPATH)
+               append_extended_header(&p, "linkpath", content, contentsize);
        write_if_needed();
 }
 
@@ -244,38 +254,60 @@ static void write_header(const char *sha1, char typeflag, const char *basepath,
                          unsigned int mode, void *buffer, unsigned long size)
 {
        unsigned int namelen; 
-       char *p, *header = NULL;
+       char *header = NULL;
        unsigned int checksum = 0;
        int i;
+       unsigned int ext_header = 0;
 
        if (typeflag == TYPEFLAG_AUTO) {
                if (S_ISDIR(mode))
                        typeflag = TYPEFLAG_DIR;
+               else if (S_ISLNK(mode))
+                       typeflag = TYPEFLAG_LNK;
                else
                        typeflag = TYPEFLAG_REG;
        }
 
        namelen = path_len(S_ISDIR(mode), basepath, prefix, path);
-       if (namelen > 500) {
+       if (namelen > 500)
                die("tar-tree: name too log of object %s\n", sha1_to_hex(sha1));
-       } else if (namelen > 100) {
-               char *sha1_hex = sha1_to_hex(sha1);
+       else if (namelen > 100)
+               ext_header |= EXT_HEADER_PATH;
+       if (typeflag == TYPEFLAG_LNK && size > 100)
+               ext_header |= EXT_HEADER_LINKPATH;
+
+       /* the extended header must be written before the normal one */
+       if (ext_header) {
                char headerfilename[51];
-               sprintf(headerfilename, "%s.paxheader", sha1_hex);
-               /* the extended header must be written before the normal one */
+               sprintf(headerfilename, "%s.paxheader", sha1_to_hex(sha1));
                write_extended_header(headerfilename, S_ISDIR(mode),
-                                     0, basepath, prefix, path,
+                                     ext_header, basepath, prefix, path,
                                      namelen, buffer, size);
+       }
 
-               header = get_record();
-               sprintf(header, "%s.data", sha1_hex);
+       header = get_record();
+
+       if (ext_header) {
+               sprintf(header, "%s.data", sha1_to_hex(sha1));
        } else {
-               p = header = get_record();
+               char *p = header;
                append_path(&p, S_ISDIR(mode), basepath, prefix, path);
        }
 
+       if (typeflag == TYPEFLAG_LNK) {
+               if (ext_header & EXT_HEADER_LINKPATH) {
+                       sprintf(&header[157], "see %s.paxheader",
+                               sha1_to_hex(sha1));
+               } else {
+                       if (buffer)
+                               strncpy(&header[157], buffer, size);
+               }
+       }
+
        if (S_ISDIR(mode))
                mode |= 0755;   /* GIT doesn't store permissions of dirs */
+       if (S_ISLNK(mode))
+               mode |= 0777;   /* ... nor of symlinks */
        sprintf(&header[100], "%07o", mode & 07777);
 
        /* XXX: should we provide more meaningful info here? */
@@ -284,7 +316,9 @@ static void write_header(const char *sha1, char typeflag, const char *basepath,
        strncpy(&header[265], "git", 31);       /* uname */
        strncpy(&header[297], "git", 31);       /* gname */
 
-       sprintf(&header[124], "%011lo", S_ISDIR(mode) ? 0 : size);
+       if (S_ISDIR(mode) || S_ISLNK(mode))
+               size = 0;
+       sprintf(&header[124], "%011lo", size);
        sprintf(&header[136], "%011lo", archive_time);
 
        header[156] = typeflag;
@@ -331,7 +365,7 @@ static void traverse_tree(void *buffer, unsigned long size,
                if (!strcmp(elttype, "tree")) {
                        this_prefix.name = path;
                        traverse_tree(eltbuf, eltsize, &this_prefix);
-               } else if (!strcmp(elttype, "blob")) {
+               } else if (!strcmp(elttype, "blob") && !S_ISLNK(mode)) {
                        write_blocked(eltbuf, eltsize);
                }
                free(eltbuf);