bisect--helper: implement "git bisect--helper"

This patch implements a new "git bisect--helper" builtin plumbing
command that will be used to migrate "git-bisect.sh" to C.

We start by implementing only the "--next-vars" option that will
read bisect refs from "refs/bisect/", and then compute the next
bisect step, and output shell variables ready to be eval'ed by
the shell.

At this step, "git bisect--helper" ignores the paths that may
have been put in "$GIT_DIR/BISECT_NAMES". This will be fixed in a
later patch.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Makefile b/Makefile
index 42cabe81620e017d522ae377874e6b1bd1f10b6f..a2bfad43bc9f695f707d2d69472eb7d1af09ca5e 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -533,6 +533,7 @@ BUILTIN_OBJS += builtin-add.o
 BUILTIN_OBJS += builtin-annotate.o
 BUILTIN_OBJS += builtin-apply.o
 BUILTIN_OBJS += builtin-archive.o
+BUILTIN_OBJS += builtin-bisect--helper.o
 BUILTIN_OBJS += builtin-blame.o
 BUILTIN_OBJS += builtin-branch.o
 BUILTIN_OBJS += builtin-bundle.o

diff --git a/bisect.c b/bisect.c
index 47120c1cd87c1df97d28c7d687bedbc69338806a..94ec011786cdff03fd143926aea7835dc2839a30 100644 (file)
--- a/bisect.c
+++ b/bisect.c
@@ -2,11 +2,18 @@
 #include "commit.h"
 #include "diff.h"
 #include "revision.h"
+#include "refs.h"
+#include "list-objects.h"
 #include "sha1-lookup.h"
 #include "bisect.h"
 
 static unsigned char (*skipped_sha1)[20];
 static int skipped_sha1_nr;
+static int skipped_sha1_alloc;
+
+static const char **rev_argv;
+static int rev_argv_nr;
+static int rev_argv_alloc;
 
 /* bits #0-15 in revision.h */
 
@@ -390,6 +397,33 @@ struct commit_list *find_bisection(struct commit_list *list,
        return best;
 }
 
+static int register_ref(const char *refname, const unsigned char *sha1,
+                       int flags, void *cb_data)
+{
+       if (!strcmp(refname, "bad")) {
+               ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
+               rev_argv[rev_argv_nr++] = xstrdup(sha1_to_hex(sha1));
+       } else if (!prefixcmp(refname, "good-")) {
+               const char *hex = sha1_to_hex(sha1);
+               char *good = xmalloc(strlen(hex) + 2);
+               *good = '^';
+               memcpy(good + 1, hex, strlen(hex) + 1);
+               ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
+               rev_argv[rev_argv_nr++] = good;
+       } else if (!prefixcmp(refname, "skip-")) {
+               ALLOC_GROW(skipped_sha1, skipped_sha1_nr + 1,
+                          skipped_sha1_alloc);
+               hashcpy(skipped_sha1[skipped_sha1_nr++], sha1);
+       }
+
+       return 0;
+}
+
+static int read_bisect_refs(void)
+{
+       return for_each_ref_in("refs/bisect/", register_ref, NULL);
+}
+
 static int skipcmp(const void *a, const void *b)
 {
        return hashcmp(a, b);
@@ -444,3 +478,37 @@ struct commit_list *filter_skipped(struct commit_list *list,
 
        return filtered;
 }
+
+int bisect_next_vars(const char *prefix)
+{
+       struct rev_info revs;
+       int reaches = 0, all = 0;
+
+       init_revisions(&revs, prefix);
+       revs.abbrev = 0;
+       revs.commit_format = CMIT_FMT_UNSPECIFIED;
+
+       /* argv[0] will be ignored by setup_revisions */
+       ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
+       rev_argv[rev_argv_nr++] = xstrdup("bisect_rev_setup");
+
+       if (read_bisect_refs())
+               die("reading bisect refs failed");
+
+       ALLOC_GROW(rev_argv, rev_argv_nr + 1, rev_argv_alloc);
+       rev_argv[rev_argv_nr++] = xstrdup("--");
+
+       setup_revisions(rev_argv_nr, rev_argv, &revs, NULL);
+
+       revs.limited = 1;
+
+       if (prepare_revision_walk(&revs))
+               die("revision walk setup failed");
+       if (revs.tree_objects)
+               mark_edges_uninteresting(revs.commits, &revs, NULL);
+
+       revs.commits = find_bisection(revs.commits, &reaches, &all,
+                                     !!skipped_sha1_nr);
+
+       return show_bisect_vars(&revs, reaches, all, 0, 1);
+}

diff --git a/bisect.h b/bisect.h
index 2489630da07bb82596de69aa0893e0e522ff8f06..05eea175f792ad3944b6e6584c4380318e4b2489 100644 (file)
--- a/bisect.h
+++ b/bisect.h
@@ -9,7 +9,14 @@ extern struct commit_list *filter_skipped(struct commit_list *list,
                                          struct commit_list **tried,
                                          int show_all);
 
+/*
+ * The "show_all" parameter should be 0 if this function is called
+ * from outside "builtin-rev-list.c" as otherwise it would use
+ * static "revs" from this file.
+ */
 extern int show_bisect_vars(struct rev_info *revs, int reaches, int all,
                            int show_all, int show_tried);
 
+extern int bisect_next_vars(const char *prefix);
+
 #endif

diff --git a/builtin-bisect--helper.c b/builtin-bisect--helper.c
new file mode 100644 (file)
index 0000000..8fe7787
--- /dev/null
+++ b/builtin-bisect--helper.c
@@ -0,0 +1,27 @@
+#include "builtin.h"
+#include "cache.h"
+#include "parse-options.h"
+#include "bisect.h"
+
+static const char * const git_bisect_helper_usage[] = {
+       "git bisect--helper --next-vars",
+       NULL
+};
+
+int cmd_bisect__helper(int argc, const char **argv, const char *prefix)
+{
+       int next_vars = 0;
+       struct option options[] = {
+               OPT_BOOLEAN(0, "next-vars", &next_vars,
+                           "output next bisect step variables"),
+               OPT_END()
+       };
+
+       argc = parse_options(argc, argv, options, git_bisect_helper_usage, 0);
+
+       if (!next_vars)
+               usage_with_options(git_bisect_helper_usage, options);
+
+       /* next-vars */
+       return bisect_next_vars(prefix);
+}

diff --git a/builtin.h b/builtin.h
index 1495cf6a20128ccffb981c3ac4d1da5469da1940..425ff8e89b361c34b3336cda58794682c66b57f3 100644 (file)
--- a/builtin.h
+++ b/builtin.h
@@ -25,6 +25,7 @@ extern int cmd_add(int argc, const char **argv, const char *prefix);
 extern int cmd_annotate(int argc, const char **argv, const char *prefix);
 extern int cmd_apply(int argc, const char **argv, const char *prefix);
 extern int cmd_archive(int argc, const char **argv, const char *prefix);
+extern int cmd_bisect__helper(int argc, const char **argv, const char *prefix);
 extern int cmd_blame(int argc, const char **argv, const char *prefix);
 extern int cmd_branch(int argc, const char **argv, const char *prefix);
 extern int cmd_bundle(int argc, const char **argv, const char *prefix);

diff --git a/git.c b/git.c
index c2b181ed78daa4510f5cfb7bbff5b78f449f872a..a553926b68f06bc9b1bd3169f6719b79ec0fd624 100644 (file)
--- a/git.c
+++ b/git.c
@@ -271,6 +271,7 @@ static void handle_internal_command(int argc, const char **argv)
                { "annotate", cmd_annotate, RUN_SETUP },
                { "apply", cmd_apply },
                { "archive", cmd_archive },
+               { "bisect--helper", cmd_bisect__helper, RUN_SETUP | NEED_WORK_TREE },
                { "blame", cmd_blame, RUN_SETUP },
                { "branch", cmd_branch, RUN_SETUP },
                { "bundle", cmd_bundle },