built-ins: trust the "prefix" from run_builtin()

Change code in "builtin/grep.c" and "builtin/ls-tree.c" to trust the
"prefix" passed from "run_builtin()". The "prefix" we get from setup.c
is either going to be NULL or a string of length >0, never "".

So we can drop the "prefix && *prefix" checks added for
"builtin/grep.c" in 0d042fecf2f (git-grep: show pathnames relative to
the current directory, 2006-08-11), and for "builtin/ls-tree.c" in
a69dd585fca (ls-tree: chomp leading directories when run from a
subdirectory, 2005-12-23).

As seen in code in revision.c that was added in cd676a51367 (diff
--relative: output paths as relative to the current subdirectory,
2008-02-12) we already have existing code that does away with this
assertion.

This makes it easier to reason about a subsequent change to the
"prefix_length" code in grep.c in a subsequent commit, and since we're
going to the trouble of doing that let's leave behind an assert() to
promise this to any future callers.

For "builtin/grep.c" it would be painful to pass the "prefix" down the
callchain of:

    cmd_grep -> grep_tree -> grep_submodule -> grep_cache -> grep_oid ->
    grep_source_name

So for the code that needs it in grep_source_name() let's add a
"grep_prefix" variable similar to the existing "ls_tree_prefix".

While at it let's move the code in cmd_ls_tree() around so that we
assign to the "ls_tree_prefix" right after declaring the variables,
and stop assigning to "prefix". We only subsequently used that
variable later in the function after clobbering it. Let's just use our
own "grep_prefix" instead.

Let's also add an assert() in git.c, so that we'll make this promise
about the "prefix" to any current and future callers, as well as to
any readers of the code.

Code history:

 * The strlen() in "grep.c" hasn't been used since 493b7a08d80 (grep:
   accept relative paths outside current working directory, 2009-09-05).

   When that code was added in 0d042fecf2f (git-grep: show pathnames
   relative to the current directory, 2006-08-11) we used the length.

   But since 493b7a08d80 we haven't used it for anything except a
   boolean check that we could have done on the "prefix" member
   itself.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/grep.c b/builtin/grep.c
index 9e34a820ad4d837937a0ecb2bc712de972506b50..d85cbabea67fbf90601fe7b76466c63b48a286bb 100644 (file)
--- a/builtin/grep.c
+++ b/builtin/grep.c
@@ -26,6 +26,8 @@
 #include "object-store.h"
 #include "packfile.h"
 
+static const char *grep_prefix;
+
 static char const * const grep_usage[] = {
        N_("git grep [<options>] [-e] <pattern> [<rev>...] [[--] <path>...]"),
        NULL
@@ -315,11 +317,11 @@ static void grep_source_name(struct grep_opt *opt, const char *filename,
        strbuf_reset(out);
 
        if (opt->null_following_name) {
-               if (opt->relative && opt->prefix_length) {
+               if (opt->relative && grep_prefix) {
                        struct strbuf rel_buf = STRBUF_INIT;
                        const char *rel_name =
                                relative_path(filename + tree_name_len,
-                                             opt->prefix, &rel_buf);
+                                             grep_prefix, &rel_buf);
 
                        if (tree_name_len)
                                strbuf_add(out, filename, tree_name_len);
@@ -332,8 +334,8 @@ static void grep_source_name(struct grep_opt *opt, const char *filename,
                return;
        }
 
-       if (opt->relative && opt->prefix_length)
-               quote_path(filename + tree_name_len, opt->prefix, out, 0);
+       if (opt->relative && grep_prefix)
+               quote_path(filename + tree_name_len, grep_prefix, out, 0);
        else
                quote_c_style(filename + tree_name_len, out, NULL, 0);
 
@@ -962,9 +964,10 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
                           PARSE_OPT_NOCOMPLETE),
                OPT_END()
        };
+       grep_prefix = prefix;
 
        git_config(grep_cmd_config, NULL);
-       grep_init(&opt, the_repository, prefix);
+       grep_init(&opt, the_repository);
 
        /*
         * If there is no -- then the paths must exist in the working

diff --git a/builtin/ls-tree.c b/builtin/ls-tree.c
index 3a442631c71a07f0d0dda791ed72af83f2b92bca..6cb554cbb0a08a881f6b85385c4b1c445589c2ee 100644 (file)
--- a/builtin/ls-tree.c
+++ b/builtin/ls-tree.c
@@ -150,7 +150,7 @@ int cmd_ls_tree(int argc, const char **argv, const char *prefix)
 
        git_config(git_default_config, NULL);
        ls_tree_prefix = prefix;
-       if (prefix && *prefix)
+       if (prefix)
                chomp_prefix = strlen(prefix);
 
        argc = parse_options(argc, argv, prefix, ls_tree_options,

diff --git a/git.c b/git.c
index edda922ce6d423b8b734b47b979f4912b9a4d281..9d257e092da2b22dfd60141a899533eb06277846 100644 (file)
--- a/git.c
+++ b/git.c
@@ -436,6 +436,7 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
        } else {
                prefix = NULL;
        }
+       assert(!prefix || *prefix);
        precompose_argv_prefix(argc, argv, NULL);
        if (use_pager == -1 && run_setup &&
                !(p->option & DELAY_PAGER_CONFIG))

diff --git a/grep.c b/grep.c
index 7bb0360869a64bca7af1e2d7faecb937a63b7910..8421dc55486b90785a936cbc1cd6e5200b36ad56 100644 (file)
--- a/grep.c
+++ b/grep.c
@@ -139,13 +139,11 @@ int grep_config(const char *var, const char *value, void *cb)
  * default values from the template we read the configuration
  * information in an earlier call to git_config(grep_config).
  */
-void grep_init(struct grep_opt *opt, struct repository *repo, const char *prefix)
+void grep_init(struct grep_opt *opt, struct repository *repo)
 {
        *opt = grep_defaults;
 
        opt->repo = repo;
-       opt->prefix = prefix;
-       opt->prefix_length = (prefix && *prefix) ? strlen(prefix) : 0;
        opt->pattern_tail = &opt->pattern_list;
        opt->header_tail = &opt->header_list;
 }

diff --git a/grep.h b/grep.h
index 400172676a19fbc953045ccbf7ece578dd01bf31..23a2a41d2c47eb161c314bbdaf430553bd98b302 100644 (file)
--- a/grep.h
+++ b/grep.h
@@ -134,8 +134,6 @@ struct grep_opt {
         */
        struct repository *repo;
 
-       const char *prefix;
-       int prefix_length;
        int linenum;
        int columnnum;
        int invert;
@@ -182,7 +180,7 @@ struct grep_opt {
 };
 
 int grep_config(const char *var, const char *value, void *);
-void grep_init(struct grep_opt *, struct repository *repo, const char *prefix);
+void grep_init(struct grep_opt *, struct repository *repo);
 void grep_commit_pattern_type(enum grep_pattern_type, struct grep_opt *opt);
 
 void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen, const char *origin, int no, enum grep_pat_token t);

diff --git a/revision.c b/revision.c
index ad4286fbdde521c3eebc048577bc61a341c9e6ee..d6e0e2b23b56b0e056269ba2e43eee86a9fb7305 100644 (file)
--- a/revision.c
+++ b/revision.c
@@ -1838,7 +1838,7 @@ void repo_init_revisions(struct repository *r,
        revs->commit_format = CMIT_FMT_DEFAULT;
        revs->expand_tabs_in_log_default = 8;
 
-       grep_init(&revs->grep_filter, revs->repo, prefix);
+       grep_init(&revs->grep_filter, revs->repo);
        revs->grep_filter.status_only = 1;
 
        repo_diff_setup(revs->repo, &revs->diffopt);