builtin-grep: unparse more command line options.

The earlier one to use external grep missed some often used options.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/builtin-grep.c b/builtin-grep.c
index 14471db..3d6e515 100644 (file)
--- a/builtin-grep.c
+++ b/builtin-grep.c
@@ -437,24 +437,73 @@ static int exec_grep(int argc, const char **argv)
 }
 
 #define MAXARGS 1000
+#define ARGBUF 4096
+#define push_arg(a) do { \
+       if (nr < MAXARGS) argv[nr++] = (a); \
+       else die("maximum number of args exceeded"); \
+       } while (0)
 
 static int external_grep(struct grep_opt *opt, const char **paths, int cached)
 {
-       int i, nr, argc, hit;
+       int i, nr, argc, hit, len;
        const char *argv[MAXARGS+1];
+       char randarg[ARGBUF];
+       char *argptr = randarg;
        struct grep_pat *p;
 
-       nr = 0;
-       argv[nr++] = "grep";
+       len = nr = 0;
+       push_arg("grep");
+       push_arg("-H");
+       if (opt->fixed)
+               push_arg("-H");
+       if (opt->linenum)
+               push_arg("-n");
+       if (opt->regflags & REG_EXTENDED)
+               push_arg("-E");
        if (opt->word_regexp)
-               argv[nr++] = "-w";
+               push_arg("-w");
        if (opt->name_only)
-               argv[nr++] = "-l";
+               push_arg("-l");
+       if (opt->unmatch_name_only)
+               push_arg("-L");
+       if (opt->count)
+               push_arg("-c");
+       if (opt->post_context || opt->pre_context) {
+               if (opt->post_context != opt->pre_context) {
+                       if (opt->pre_context) {
+                               push_arg("-B");
+                               len += snprintf(argptr, sizeof(randarg)-len,
+                                               "%u", opt->pre_context);
+                               if (sizeof(randarg) <= len)
+                                       die("maximum length of args exceeded");
+                               push_arg(argptr);
+                               argptr += len;
+                       }
+                       if (opt->post_context) {
+                               push_arg("-A");
+                               len += snprintf(argptr, sizeof(randarg)-len,
+                                               "%u", opt->post_context);
+                               if (sizeof(randarg) <= len)
+                                       die("maximum length of args exceeded");
+                               push_arg(argptr);
+                               argptr += len;
+                       }
+               }
+               else {
+                       push_arg("-C");
+                       len += snprintf(argptr, sizeof(randarg)-len,
+                                       "%u", opt->post_context);
+                       if (sizeof(randarg) <= len)
+                               die("maximum length of args exceeded");
+                       push_arg(argptr);
+                       argptr += len;
+               }
+       }
        for (p = opt->pattern_list; p; p = p->next) {
-               argv[nr++] = "-e";
-               argv[nr++] = p->pattern;
+               push_arg("-e");
+               push_arg(p->pattern);
        }
-       argv[nr++] = "--";
+       push_arg("--");
 
        hit = 0;
        argc = nr;