There are currently 115 commands built into the git executable.
Before this commit, it was iterated over these commands in a linear
order, i.e. each command was checked.

As it turns out the commands are already sorted alphabetically, it is easy
to perform a binary search instead of linear searching.
This results in 7 lookups in the worst case.

Signed-off-by: Stefan Beller <stefanbel...@googlemail.com>
---
 git.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/git.c b/git.c
index 2025f77..6d4de2b 100644
--- a/git.c
+++ b/git.c
@@ -309,9 +309,14 @@ static int run_builtin(struct cmd_struct *p, int argc, 
const char **argv)
        return 0;
 }
 
+static int compare_internal_command(const void *name, const void *cmd) {
+       return strcmp((const char*)name, ((const struct cmd_struct*)cmd)->cmd);
+}
+
 static void handle_internal_command(int argc, const char **argv)
 {
        const char *cmd = argv[0];
+       /* commands must be sorted alphabetically for binary search */
        static struct cmd_struct commands[] = {
                { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
                { "annotate", cmd_annotate, RUN_SETUP },
@@ -447,12 +452,12 @@ static void handle_internal_command(int argc, const char 
**argv)
                argv[0] = cmd = "help";
        }
 
-       for (i = 0; i < ARRAY_SIZE(commands); i++) {
-               struct cmd_struct *p = commands+i;
-               if (strcmp(p->cmd, cmd))
-                       continue;
+       struct cmd_struct *p = bsearch(cmd, commands,
+                               ARRAY_SIZE(commands), sizeof(struct cmd_struct),
+                               compare_internal_command);
+
+       if (p)
                exit(run_builtin(p, argc, argv));
-       }
 }
 
 static void execv_dashed_external(const char **argv)
-- 
1.8.4.rc0.1.g8f6a3e5

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