commit: allow partial commits with relative paths

In order to do partial commits, git-commit overlays a tree on the
cache and checks pathspecs against the result. Currently, the
overlaying is done using "prefix" which prevents relative pathspecs
with ".." and absolute pathspec from matching when they refer to
files not under "prefix" and absent from the index, but still in
the tree (i.e.  files staged for removal).

The point of providing a prefix at all is performance optimization.
If we say there is no common prefix for the files of interest, then
we have to read the entire tree into the index.

But even if we cannot use the working directory as a prefix, we can
still figure out if there is a common prefix for all given paths,
and use that instead. The pathspec_prefix() routine from ls-files.c
does exactly that.

Any use of global variables is removed from pathspec_prefix() so
that it can be called from commit.c.

Reported-by: Reuben Thomas <rrt@sc3d.org>
Analyzed-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/commit.c b/builtin/commit.c
index e1af9b19f0be71484ae9341762dc2bf89cabb70c..cb738574f729e91ff239f12db3f3f1ef1ef9570c 100644 (file)
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -256,8 +256,10 @@ static int list_paths(struct string_list *list, const char *with_tree,
                ;
        m = xcalloc(1, i);
 
-       if (with_tree)
-               overlay_tree_on_cache(with_tree, prefix);
+       if (with_tree) {
+               const char *max_prefix = pathspec_prefix(prefix, pattern);
+               overlay_tree_on_cache(with_tree, max_prefix);
+       }
 
        for (i = 0; i < active_nr; i++) {
                struct cache_entry *ce = active_cache[i];

diff --git a/builtin/ls-files.c b/builtin/ls-files.c
index 15701233e29b240cfa1abdb56bd489306e74c677..0e98bff0c46035162fc424418cc434b52299c1cc 100644 (file)
--- a/builtin/ls-files.c
+++ b/builtin/ls-files.c
@@ -276,41 +276,6 @@ static void prune_cache(const char *prefix)
        active_nr = last;
 }
 
-static const char *pathspec_prefix(const char *prefix)
-{
-       const char **p, *n, *prev;
-       unsigned long max;
-
-       if (!pathspec) {
-               max_prefix_len = prefix ? strlen(prefix) : 0;
-               return prefix;
-       }
-
-       prev = NULL;
-       max = PATH_MAX;
-       for (p = pathspec; (n = *p) != NULL; p++) {
-               int i, len = 0;
-               for (i = 0; i < max; i++) {
-                       char c = n[i];
-                       if (prev && prev[i] != c)
-                               break;
-                       if (!c || c == '*' || c == '?')
-                               break;
-                       if (c == '/')
-                               len = i+1;
-               }
-               prev = n;
-               if (len < max) {
-                       max = len;
-                       if (!max)
-                               break;
-               }
-       }
-
-       max_prefix_len = max;
-       return max ? xmemdupz(prev, max) : NULL;
-}
-
 static void strip_trailing_slash_from_submodules(void)
 {
        const char **p;
@@ -576,7 +541,8 @@ int cmd_ls_files(int argc, const char **argv, const char *cmd_prefix)
                strip_trailing_slash_from_submodules();
 
        /* Find common prefix for all pathspec's */
-       max_prefix = pathspec_prefix(prefix);
+       max_prefix = pathspec_prefix(prefix, pathspec);
+       max_prefix_len = max_prefix ? strlen(max_prefix) : 0;
 
        /* Treat unmatching pathspec elements as errors */
        if (pathspec && error_unmatch) {

diff --git a/cache.h b/cache.h
index e11cf6ab1c73ac97c94e76e8c8699d55af95b978..553a6ebd4b5cf1fb7269b0dd6a9589d2c638a7c3 100644 (file)
--- a/cache.h
+++ b/cache.h
@@ -426,6 +426,7 @@ extern void set_git_work_tree(const char *tree);
 #define ALTERNATE_DB_ENVIRONMENT "GIT_ALTERNATE_OBJECT_DIRECTORIES"
 
 extern const char **get_pathspec(const char *prefix, const char **pathspec);
+extern const char *pathspec_prefix(const char *prefix, const char **pathspec);
 extern void setup_work_tree(void);
 extern const char *setup_git_directory_gently(int *);
 extern const char *setup_git_directory(void);

diff --git a/setup.c b/setup.c
index ce87900ce3c68ace0f231827bdda0e9a65ef15b3..699fcf096d98f9875586cf07297eb87b431f5961 100644 (file)
--- a/setup.c
+++ b/setup.c
@@ -264,6 +264,38 @@ const char **get_pathspec(const char *prefix, const char **pathspec)
        return pathspec;
 }
 
+const char *pathspec_prefix(const char *prefix, const char **pathspec)
+{
+       const char **p, *n, *prev;
+       unsigned long max;
+
+       if (!pathspec)
+               return prefix ? xmemdupz(prefix, strlen(prefix)) : NULL;
+
+       prev = NULL;
+       max = PATH_MAX;
+       for (p = pathspec; (n = *p) != NULL; p++) {
+               int i, len = 0;
+               for (i = 0; i < max; i++) {
+                       char c = n[i];
+                       if (prev && prev[i] != c)
+                               break;
+                       if (!c || c == '*' || c == '?')
+                               break;
+                       if (c == '/')
+                               len = i+1;
+               }
+               prev = n;
+               if (len < max) {
+                       max = len;
+                       if (!max)
+                               break;
+               }
+       }
+
+       return max ? xmemdupz(prev, max) : NULL;
+}
+
 /*
  * Test if it looks like we're at a git directory.
  * We want to see: