compat: Add simplified merge sort implementation from glibc

diff --git a/builtin-describe.c b/builtin-describe.c
index 669110cb0645629ca5b152d8328aa91d63be1550..7a148a2c26591d82e6057d610182445eae5fe171 100644 (file)
--- a/builtin-describe.c
+++ b/builtin-describe.c
@@ -4,12 +4,15 @@
 #include "refs.h"
 #include "builtin.h"
 #include "exec_cmd.h"
+#include "parse-options.h"
 
 #define SEEN           (1u<<0)
 #define MAX_TAGS       (FLAG_BITS - 1)
 
-static const char describe_usage[] =
-"git-describe [--all] [--tags] [--abbrev=<n>] <committish>*";
+static const char * const describe_usage[] = {
+       "git-describe [options] <committish>*",
+       NULL
+};
 
 static int debug;      /* Display lots of verbose info */
 static int all;        /* Default to annotated tags only */
@@ -242,57 +245,44 @@ static void describe(const char *arg, int last_one)
 
 int cmd_describe(int argc, const char **argv, const char *prefix)
 {
-       int i;
        int contains = 0;
+       struct option options[] = {
+               OPT_BOOLEAN(0, "contains",   &contains, "find the tag that comes after the commit"),
+               OPT_BOOLEAN(0, "debug",      &debug, "debug search strategy on stderr"),
+               OPT_BOOLEAN(0, "all",        &all, "use any ref in .git/refs"),
+               OPT_BOOLEAN(0, "tags",       &tags, "use any tag in .git/refs/tags"),
+               OPT__ABBREV(&abbrev),
+               OPT_INTEGER(0, "candidates", &max_candidates,
+                                       "consider <n> most recent tags (default: 10)"),
+               OPT_END(),
+       };
 
-       for (i = 1; i < argc; i++) {
-               const char *arg = argv[i];
-
-               if (*arg != '-')
-                       break;
-               else if (!strcmp(arg, "--contains"))
-                       contains = 1;
-               else if (!strcmp(arg, "--debug"))
-                       debug = 1;
-               else if (!strcmp(arg, "--all"))
-                       all = 1;
-               else if (!strcmp(arg, "--tags"))
-                       tags = 1;
-               else if (!prefixcmp(arg, "--abbrev=")) {
-                       abbrev = strtoul(arg + 9, NULL, 10);
-                       if (abbrev != 0 && (abbrev < MINIMUM_ABBREV || 40 < abbrev))
-                               abbrev = DEFAULT_ABBREV;
-               }
-               else if (!prefixcmp(arg, "--candidates=")) {
-                       max_candidates = strtoul(arg + 13, NULL, 10);
-                       if (max_candidates < 1)
-                               max_candidates = 1;
-                       else if (max_candidates > MAX_TAGS)
-                               max_candidates = MAX_TAGS;
-               }
-               else
-                       usage(describe_usage);
-       }
+       argc = parse_options(argc, argv, options, describe_usage, 0);
+       if (max_candidates < 1)
+               max_candidates = 1;
+       else if (max_candidates > MAX_TAGS)
+               max_candidates = MAX_TAGS;
 
        save_commit_buffer = 0;
 
        if (contains) {
-               const char **args = xmalloc((4 + argc - i) * sizeof(char*));
-               args[0] = "name-rev";
-               args[1] = "--name-only";
-               args[2] = "--tags";
-               memcpy(args + 3, argv + i, (argc - i) * sizeof(char*));
-               args[3 + argc - i] = NULL;
-               return cmd_name_rev(3 + argc - i, args, prefix);
+               const char **args = xmalloc((4 + argc) * sizeof(char*));
+               int i = 0;
+               args[i++] = "name-rev";
+               args[i++] = "--name-only";
+               if (!all)
+                       args[i++] = "--tags";
+               memcpy(args + i, argv, argc * sizeof(char*));
+               args[i + argc] = NULL;
+               return cmd_name_rev(i + argc, args, prefix);
        }
 
-       if (argc <= i)
+       if (argc == 0) {
                describe("HEAD", 1);
-       else
-               while (i < argc) {
-                       describe(argv[i], (i == argc - 1));
-                       i++;
+       } else {
+               while (argc-- > 0) {
+                       describe(*argv++, argc == 0);
                }
-
+       }
        return 0;
 }