[PATCH] ls-tree for listing trees

ls-tree tool provides just a way to export the binary tree objects
to a usable text format. This is bound to be useful in variety
of scripts, although none of those I have currently uses it.
But e.g. the simple script I've sent to HPA for purging the object
database uses it.

Signed-off-by: Petr Baudis <pasky@ucw.cz>

diff --git a/Makefile b/Makefile
index dc6e5ab..7c2c1b5 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,9 +1,9 @@
 CFLAGS=-g -O3 -Wall
 CC=gcc
 
-PROG=  update-cache show-diff init-db write-tree read-tree commit-tree \
+PROG=   update-cache show-diff init-db write-tree read-tree commit-tree \
        cat-file fsck-cache checkout-cache diff-tree rev-tree show-files \
-       check-files
+       check-files ls-tree
 
 all: $(PROG)
 
@@ -50,6 +50,9 @@ show-files: show-files.o read-cache.o
 check-files: check-files.o read-cache.o
        $(CC) $(CFLAGS) -o check-files check-files.o read-cache.o $(LIBS)
 
+ls-tree: ls-tree.o read-cache.o
+       $(CC) $(CFLAGS) -o ls-tree ls-tree.o read-cache.o $(LIBS)
+
 read-cache.o: cache.h
 show-diff.o: cache.h
 

diff --git a/ls-tree.c b/ls-tree.c
new file mode 100644 (file)
index 0000000..05c743a
--- /dev/null
+++ b/ls-tree.c
@@ -0,0 +1,53 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#include "cache.h"
+
+static int list(unsigned char *sha1)
+{
+       void *buffer;
+       unsigned long size;
+       char type[20];
+
+       buffer = read_sha1_file(sha1, type, &size);
+       if (!buffer)
+               usage("unable to read sha1 file");
+       if (strcmp(type, "tree"))
+               usage("expected a 'tree' node");
+       while (size) {
+               int len = strlen(buffer)+1;
+               unsigned char *sha1 = buffer + len;
+               char *path = strchr(buffer, ' ')+1;
+               unsigned int mode;
+               unsigned char *type;
+
+               if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
+                       usage("corrupt 'tree' file");
+               buffer = sha1 + 20;
+               size -= len + 20;
+               /* XXX: We do some ugly mode heuristics here.
+                * It seems not worth it to read each file just to get this
+                * and the file size. -- pasky@ucw.cz */
+               type = S_ISDIR(mode) ? "tree" : "blob";
+               printf("%03o\t%s\t%s\t%s\n", mode, type, sha1_to_hex(sha1), path);
+       }
+       return 0;
+}
+
+int main(int argc, char **argv)
+{
+       unsigned char sha1[20];
+
+       if (argc != 2)
+               usage("ls-tree <key>");
+       if (get_sha1_hex(argv[1], sha1) < 0)
+               usage("ls-tree <key>");
+       sha1_file_directory = getenv(DB_ENVIRONMENT);
+       if (!sha1_file_directory)
+               sha1_file_directory = DEFAULT_DB_ENVIRONMENT;
+       if (list(sha1) < 0)
+               usage("list failed");
+       return 0;
+}