X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=builtin-grep.c;h=ef299108f529fa5fa931d765828f04535c3a6351;hb=3562198b7da7ef6597af27b3a7fcaeee41608999;hp=e13cb31f2b9dd63d335437fb5b1c9b0b06fbf188;hpb=e660e11b202f12d15cfe8089909a307b1900c03a;p=git.git diff --git a/builtin-grep.c b/builtin-grep.c index e13cb31f2..ef299108f 100644 --- a/builtin-grep.c +++ b/builtin-grep.c @@ -12,6 +12,14 @@ #include "builtin.h" #include "grep.h" +#ifndef NO_EXTERNAL_GREP +#ifdef __unix__ +#define NO_EXTERNAL_GREP 0 +#else +#define NO_EXTERNAL_GREP 1 +#endif +#endif + /* * git grep pathspecs are somewhat different from diff-tree pathspecs; * pathname wildcards are allowed. @@ -153,7 +161,7 @@ static int grep_file(struct grep_opt *opt, const char *filename) return i; } -#ifdef __unix__ +#if !NO_EXTERNAL_GREP static int exec_grep(int argc, const char **argv) { pid_t pid; @@ -187,6 +195,78 @@ static int exec_grep(int argc, const char **argv) else die("maximum number of args exceeded"); \ } while (0) +/* + * If you send a singleton filename to grep, it does not give + * the name of the file. GNU grep has "-H" but we would want + * that behaviour in a portable way. + * + * So we keep two pathnames in argv buffer unsent to grep in + * the main loop if we need to do more than one grep. + */ +static int flush_grep(struct grep_opt *opt, + int argc, int arg0, const char **argv, int *kept) +{ + int status; + int count = argc - arg0; + const char *kept_0 = NULL; + + if (count <= 2) { + /* + * Because we keep at least 2 paths in the call from + * the main loop (i.e. kept != NULL), and MAXARGS is + * far greater than 2, this usually is a call to + * conclude the grep. However, the user could attempt + * to overflow the argv buffer by giving too many + * options to leave very small number of real + * arguments even for the call in the main loop. + */ + if (kept) + die("insanely many options to grep"); + + /* + * If we have two or more paths, we do not have to do + * anything special, but we need to push /dev/null to + * get "-H" behaviour of GNU grep portably but when we + * are not doing "-l" nor "-L" nor "-c". + */ + if (count == 1 && + !opt->name_only && + !opt->unmatch_name_only && + !opt->count) { + argv[argc++] = "/dev/null"; + argv[argc] = NULL; + } + } + + else if (kept) { + /* + * Called because we found many paths and haven't finished + * iterating over the cache yet. We keep two paths + * for the concluding call. argv[argc-2] and argv[argc-1] + * has the last two paths, so save the first one away, + * replace it with NULL while sending the list to grep, + * and recover them after we are done. + */ + *kept = 2; + kept_0 = argv[argc-2]; + argv[argc-2] = NULL; + argc -= 2; + } + + status = exec_grep(argc, argv); + + if (kept_0) { + /* + * Then recover them. Now the last arg is beyond the + * terminating NULL which is at argc, and the second + * from the last is what we saved away in kept_0 + */ + argv[arg0++] = kept_0; + argv[arg0] = argv[argc+1]; + } + return status; +} + static int external_grep(struct grep_opt *opt, const char **paths, int cached) { int i, nr, argc, hit, len, status; @@ -222,7 +302,7 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached) if (opt->pre_context) { push_arg("-B"); len += snprintf(argptr, sizeof(randarg)-len, - "%u", opt->pre_context); + "%u", opt->pre_context) + 1; if (sizeof(randarg) <= len) die("maximum length of args exceeded"); push_arg(argptr); @@ -231,7 +311,7 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached) if (opt->post_context) { push_arg("-A"); len += snprintf(argptr, sizeof(randarg)-len, - "%u", opt->post_context); + "%u", opt->post_context) + 1; if (sizeof(randarg) <= len) die("maximum length of args exceeded"); push_arg(argptr); @@ -241,7 +321,7 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached) else { push_arg("-C"); len += snprintf(argptr, sizeof(randarg)-len, - "%u", opt->post_context); + "%u", opt->post_context) + 1; if (sizeof(randarg) <= len) die("maximum length of args exceeded"); push_arg(argptr); @@ -253,23 +333,13 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached) push_arg(p->pattern); } - /* - * To make sure we get the header printed out when we want it, - * add /dev/null to the paths to grep. This is unnecessary - * (and wrong) with "-l" or "-L", which always print out the - * name anyway. - * - * GNU grep has "-H", but this is portable. - */ - if (!opt->name_only && !opt->unmatch_name_only) - push_arg("/dev/null"); - hit = 0; argc = nr; for (i = 0; i < active_nr; i++) { struct cache_entry *ce = active_cache[i]; char *name; - if (!S_ISREG(ntohl(ce->ce_mode))) + int kept; + if (!S_ISREG(ce->ce_mode)) continue; if (!pathspec_matches(paths, ce->name)) continue; @@ -281,12 +351,12 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached) memcpy(name + 2, ce->name, len + 1); } argv[argc++] = name; - if (argc < MAXARGS && !ce_stage(ce)) - continue; - status = exec_grep(argc, argv); - if (0 < status) - hit = 1; - argc = nr; + if (MAXARGS <= argc) { + status = flush_grep(opt, argc, nr, argv, &kept); + if (0 < status) + hit = 1; + argc = nr + kept; + } if (ce_stage(ce)) { do { i++; @@ -296,7 +366,7 @@ static int external_grep(struct grep_opt *opt, const char **paths, int cached) } } if (argc > nr) { - status = exec_grep(argc, argv); + status = flush_grep(opt, argc, nr, argv, NULL); if (0 < status) hit = 1; } @@ -310,7 +380,7 @@ static int grep_cache(struct grep_opt *opt, const char **paths, int cached) int nr; read_cache(); -#ifdef __unix__ +#if !NO_EXTERNAL_GREP /* * Use the external "grep" command for the case where * we grep through the checked-out files. It tends to @@ -325,7 +395,7 @@ static int grep_cache(struct grep_opt *opt, const char **paths, int cached) for (nr = 0; nr < active_nr; nr++) { struct cache_entry *ce = active_cache[nr]; - if (!S_ISREG(ntohl(ce->ce_mode))) + if (!S_ISREG(ce->ce_mode)) continue; if (!pathspec_matches(paths, ce->name)) continue; @@ -516,6 +586,7 @@ int cmd_grep(int argc, const char **argv, const char *prefix) continue; } if (!strcmp("-l", arg) || + !strcmp("--name-only", arg) || !strcmp("--files-with-matches", arg)) { opt.name_only = 1; continue; @@ -582,7 +653,7 @@ int cmd_grep(int argc, const char **argv, const char *prefix) die("'%s': %s", argv[1], strerror(errno)); while (fgets(buf, sizeof(buf), patterns)) { int len = strlen(buf); - if (buf[len-1] == '\n') + if (len && buf[len-1] == '\n') buf[len-1] = 0; /* ignore empty line like grep does */ if (!buf[0])