t7810: avoid unportable use of "echo"
[gitweb.git] / grep.c
diff --git a/grep.c b/grep.c
index 543b1d53784c16020dea089f23c431c7f2608425..d03d9e24c23eff2d60ae7226a412f3ccf66670fd 100644 (file)
--- a/grep.c
+++ b/grep.c
@@ -7,6 +7,7 @@ void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field fie
 {
        struct grep_pat *p = xcalloc(1, sizeof(*p));
        p->pattern = pat;
+       p->patternlen = strlen(pat);
        p->origin = "header";
        p->no = 0;
        p->token = GREP_PATTERN_HEAD;
@@ -18,9 +19,16 @@ void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field fie
 
 void append_grep_pattern(struct grep_opt *opt, const char *pat,
                         const char *origin, int no, enum grep_pat_token t)
+{
+       append_grep_pat(opt, pat, strlen(pat), origin, no, t);
+}
+
+void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen,
+                    const char *origin, int no, enum grep_pat_token t)
 {
        struct grep_pat *p = xcalloc(1, sizeof(*p));
        p->pattern = pat;
+       p->patternlen = patlen;
        p->origin = origin;
        p->no = no;
        p->token = t;
@@ -44,13 +52,91 @@ struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
                        append_header_grep_pattern(ret, pat->field,
                                                   pat->pattern);
                else
-                       append_grep_pattern(ret, pat->pattern, pat->origin,
-                                           pat->no, pat->token);
+                       append_grep_pat(ret, pat->pattern, pat->patternlen,
+                                       pat->origin, pat->no, pat->token);
        }
 
        return ret;
 }
 
+static NORETURN void compile_regexp_failed(const struct grep_pat *p,
+               const char *error)
+{
+       char where[1024];
+
+       if (p->no)
+               sprintf(where, "In '%s' at %d, ", p->origin, p->no);
+       else if (p->origin)
+               sprintf(where, "%s, ", p->origin);
+       else
+               where[0] = 0;
+
+       die("%s'%s': %s", where, p->pattern, error);
+}
+
+#ifdef USE_LIBPCRE
+static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
+{
+       const char *error;
+       int erroffset;
+       int options = 0;
+
+       if (opt->ignore_case)
+               options |= PCRE_CASELESS;
+
+       p->pcre_regexp = pcre_compile(p->pattern, options, &error, &erroffset,
+                       NULL);
+       if (!p->pcre_regexp)
+               compile_regexp_failed(p, error);
+
+       p->pcre_extra_info = pcre_study(p->pcre_regexp, 0, &error);
+       if (!p->pcre_extra_info && error)
+               die("%s", error);
+}
+
+static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
+               regmatch_t *match, int eflags)
+{
+       int ovector[30], ret, flags = 0;
+
+       if (eflags & REG_NOTBOL)
+               flags |= PCRE_NOTBOL;
+
+       ret = pcre_exec(p->pcre_regexp, p->pcre_extra_info, line, eol - line,
+                       0, flags, ovector, ARRAY_SIZE(ovector));
+       if (ret < 0 && ret != PCRE_ERROR_NOMATCH)
+               die("pcre_exec failed with error code %d", ret);
+       if (ret > 0) {
+               ret = 0;
+               match->rm_so = ovector[0];
+               match->rm_eo = ovector[1];
+       }
+
+       return ret;
+}
+
+static void free_pcre_regexp(struct grep_pat *p)
+{
+       pcre_free(p->pcre_regexp);
+       pcre_free(p->pcre_extra_info);
+}
+#else /* !USE_LIBPCRE */
+static void compile_pcre_regexp(struct grep_pat *p, const struct grep_opt *opt)
+{
+       die("cannot use Perl-compatible regexes when not compiled with USE_LIBPCRE");
+}
+
+static int pcrematch(struct grep_pat *p, const char *line, const char *eol,
+               regmatch_t *match, int eflags)
+{
+       return 1;
+}
+
+static void free_pcre_regexp(struct grep_pat *p)
+{
+}
+#endif /* !USE_LIBPCRE */
+
 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 {
        int err;
@@ -62,20 +148,17 @@ static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
        if (p->fixed)
                return;
 
+       if (opt->pcre) {
+               compile_pcre_regexp(p, opt);
+               return;
+       }
+
        err = regcomp(&p->regexp, p->pattern, opt->regflags);
        if (err) {
                char errbuf[1024];
-               char where[1024];
-               if (p->no)
-                       sprintf(where, "In '%s' at %d, ",
-                               p->origin, p->no);
-               else if (p->origin)
-                       sprintf(where, "%s, ", p->origin);
-               else
-                       where[0] = 0;
                regerror(err, &p->regexp, errbuf, 1024);
                regfree(&p->regexp);
-               die("%s'%s': %s", where, p->pattern, errbuf);
+               compile_regexp_failed(p, errbuf);
        }
 }
 
@@ -181,29 +264,73 @@ static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
        return compile_pattern_or(list);
 }
 
-void compile_grep_patterns(struct grep_opt *opt)
+static struct grep_expr *grep_true_expr(void)
+{
+       struct grep_expr *z = xcalloc(1, sizeof(*z));
+       z->node = GREP_NODE_TRUE;
+       return z;
+}
+
+static struct grep_expr *grep_or_expr(struct grep_expr *left, struct grep_expr *right)
+{
+       struct grep_expr *z = xcalloc(1, sizeof(*z));
+       z->node = GREP_NODE_OR;
+       z->u.binary.left = left;
+       z->u.binary.right = right;
+       return z;
+}
+
+static struct grep_expr *prep_header_patterns(struct grep_opt *opt)
 {
        struct grep_pat *p;
-       struct grep_expr *header_expr = NULL;
-
-       if (opt->header_list) {
-               p = opt->header_list;
-               header_expr = compile_pattern_expr(&p);
-               if (p)
-                       die("incomplete pattern expression: %s", p->pattern);
-               for (p = opt->header_list; p; p = p->next) {
-                       switch (p->token) {
-                       case GREP_PATTERN: /* atom */
-                       case GREP_PATTERN_HEAD:
-                       case GREP_PATTERN_BODY:
-                               compile_regexp(p, opt);
-                               break;
-                       default:
-                               opt->extended = 1;
-                               break;
-                       }
+       struct grep_expr *header_expr;
+       struct grep_expr *(header_group[GREP_HEADER_FIELD_MAX]);
+       enum grep_header_field fld;
+
+       if (!opt->header_list)
+               return NULL;
+       p = opt->header_list;
+       for (p = opt->header_list; p; p = p->next) {
+               if (p->token != GREP_PATTERN_HEAD)
+                       die("bug: a non-header pattern in grep header list.");
+               if (p->field < 0 || GREP_HEADER_FIELD_MAX <= p->field)
+                       die("bug: unknown header field %d", p->field);
+               compile_regexp(p, opt);
+       }
+
+       for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++)
+               header_group[fld] = NULL;
+
+       for (p = opt->header_list; p; p = p->next) {
+               struct grep_expr *h;
+               struct grep_pat *pp = p;
+
+               h = compile_pattern_atom(&pp);
+               if (!h || pp != p->next)
+                       die("bug: malformed header expr");
+               if (!header_group[p->field]) {
+                       header_group[p->field] = h;
+                       continue;
                }
+               header_group[p->field] = grep_or_expr(h, header_group[p->field]);
+       }
+
+       header_expr = NULL;
+
+       for (fld = 0; fld < GREP_HEADER_FIELD_MAX; fld++) {
+               if (!header_group[fld])
+                       continue;
+               if (!header_expr)
+                       header_expr = grep_true_expr();
+               header_expr = grep_or_expr(header_group[fld], header_expr);
        }
+       return header_expr;
+}
+
+void compile_grep_patterns(struct grep_opt *opt)
+{
+       struct grep_pat *p;
+       struct grep_expr *header_expr = prep_header_patterns(opt);
 
        for (p = opt->pattern_list; p; p = p->next) {
                switch (p->token) {
@@ -223,9 +350,6 @@ void compile_grep_patterns(struct grep_opt *opt)
        else if (!opt->extended)
                return;
 
-       /* Then bundle them up in an expression.
-        * A classic recursive descent parser would do.
-        */
        p = opt->pattern_list;
        if (p)
                opt->pattern_expression = compile_pattern_expr(&p);
@@ -235,22 +359,18 @@ void compile_grep_patterns(struct grep_opt *opt)
        if (!header_expr)
                return;
 
-       if (opt->pattern_expression) {
-               struct grep_expr *z;
-               z = xcalloc(1, sizeof(*z));
-               z->node = GREP_NODE_OR;
-               z->u.binary.left = opt->pattern_expression;
-               z->u.binary.right = header_expr;
-               opt->pattern_expression = z;
-       } else {
+       if (!opt->pattern_expression)
                opt->pattern_expression = header_expr;
-       }
+       else
+               opt->pattern_expression = grep_or_expr(opt->pattern_expression,
+                                                      header_expr);
        opt->all_match = 1;
 }
 
 static void free_pattern_expr(struct grep_expr *x)
 {
        switch (x->node) {
+       case GREP_NODE_TRUE:
        case GREP_NODE_ATOM:
                break;
        case GREP_NODE_NOT:
@@ -275,7 +395,10 @@ void free_grep_patterns(struct grep_opt *opt)
                case GREP_PATTERN: /* atom */
                case GREP_PATTERN_HEAD:
                case GREP_PATTERN_BODY:
-                       regfree(&p->regexp);
+                       if (p->pcre_regexp)
+                               free_pcre_regexp(p);
+                       else
+                               regfree(&p->regexp);
                        break;
                default:
                        break;
@@ -329,14 +452,21 @@ static void show_name(struct grep_opt *opt, const char *name)
        opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
 }
 
-
-static int fixmatch(const char *pattern, char *line, int ignore_case, regmatch_t *match)
+static int fixmatch(struct grep_pat *p, char *line, char *eol,
+                   regmatch_t *match)
 {
        char *hit;
-       if (ignore_case)
-               hit = strcasestr(line, pattern);
-       else
-               hit = strstr(line, pattern);
+
+       if (p->ignore_case) {
+               char *s = line;
+               do {
+                       hit = strcasestr(s, p->pattern);
+                       if (hit)
+                               break;
+                       s += strlen(s) + 1;
+               } while (s < eol);
+       } else
+               hit = memmem(line, eol - line, p->pattern, p->patternlen);
 
        if (!hit) {
                match->rm_so = match->rm_eo = -1;
@@ -344,11 +474,37 @@ static int fixmatch(const char *pattern, char *line, int ignore_case, regmatch_t
        }
        else {
                match->rm_so = hit - line;
-               match->rm_eo = match->rm_so + strlen(pattern);
+               match->rm_eo = match->rm_so + p->patternlen;
                return 0;
        }
 }
 
+static int regmatch(const regex_t *preg, char *line, char *eol,
+                   regmatch_t *match, int eflags)
+{
+#ifdef REG_STARTEND
+       match->rm_so = 0;
+       match->rm_eo = eol - line;
+       eflags |= REG_STARTEND;
+#endif
+       return regexec(preg, line, 1, match, eflags);
+}
+
+static int patmatch(struct grep_pat *p, char *line, char *eol,
+                   regmatch_t *match, int eflags)
+{
+       int hit;
+
+       if (p->fixed)
+               hit = !fixmatch(p, line, eol, match);
+       else if (p->pcre_regexp)
+               hit = !pcrematch(p, line, eol, match, eflags);
+       else
+               hit = !regmatch(&p->regexp, line, eol, match, eflags);
+
+       return hit;
+}
+
 static int strip_timestamp(char *bol, char **eol_p)
 {
        char *eol = *eol_p;
@@ -398,10 +554,7 @@ static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
        }
 
  again:
-       if (p->fixed)
-               hit = !fixmatch(p->pattern, bol, p->ignore_case, pmatch);
-       else
-               hit = !regexec(&p->regexp, bol, 1, pmatch, eflags);
+       hit = patmatch(p, bol, eol, pmatch, eflags);
 
        if (hit && p->word_regexp) {
                if ((pmatch[0].rm_so < 0) ||
@@ -461,6 +614,9 @@ static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
        if (!x)
                die("Not a valid grep expression");
        switch (x->node) {
+       case GREP_NODE_TRUE:
+               h = 1;
+               break;
        case GREP_NODE_ATOM:
                h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
                break;
@@ -725,17 +881,7 @@ static int look_ahead(struct grep_opt *opt,
                int hit;
                regmatch_t m;
 
-               if (p->fixed)
-                       hit = !fixmatch(p->pattern, bol, p->ignore_case, &m);
-               else {
-#ifdef REG_STARTEND
-                       m.rm_so = 0;
-                       m.rm_eo = *left_p;
-                       hit = !regexec(&p->regexp, bol, 1, &m, REG_STARTEND);
-#else
-                       hit = !regexec(&p->regexp, bol, 1, &m, 0);
-#endif
-               }
+               hit = patmatch(p, bol, bol + *left_p, &m, 0);
                if (!hit || m.rm_so < 0 || m.rm_eo < 0)
                        continue;
                if (earliest < 0 || m.rm_so < earliest)
@@ -800,17 +946,19 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                opt->show_hunk_mark = 1;
        opt->last_shown = 0;
 
-       if (buffer_is_binary(buf, size)) {
-               switch (opt->binary) {
-               case GREP_BINARY_DEFAULT:
+       switch (opt->binary) {
+       case GREP_BINARY_DEFAULT:
+               if (buffer_is_binary(buf, size))
                        binary_match_only = 1;
-                       break;
-               case GREP_BINARY_NOMATCH:
+               break;
+       case GREP_BINARY_NOMATCH:
+               if (buffer_is_binary(buf, size))
                        return 0; /* Assume unmatch */
-                       break;
-               default:
-                       break;
-               }
+               break;
+       case GREP_BINARY_TEXT:
+               break;
+       default:
+               die("bug: unknown binary handling mode");
        }
 
        memset(&xecfg, 0, sizeof(xecfg));
@@ -830,7 +978,7 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                int hit;
 
                /*
-                * look_ahead() skips quicly to the line that possibly
+                * look_ahead() skips quickly to the line that possibly
                 * has the next hit; don't call it if we need to do
                 * something more than just skipping the current line
                 * in response to an unmatch for the current line.  E.g.
@@ -871,6 +1019,12 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                        count++;
                        if (opt->status_only)
                                return 1;
+                       if (opt->name_only) {
+                               show_name(opt, name);
+                               return 1;
+                       }
+                       if (opt->count)
+                               goto next_line;
                        if (binary_match_only) {
                                opt->output(opt, "Binary file ", 12);
                                output_color(opt, name, strlen(name),
@@ -878,22 +1032,14 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                                opt->output(opt, " matches\n", 9);
                                return 1;
                        }
-                       if (opt->name_only) {
-                               show_name(opt, name);
-                               return 1;
-                       }
                        /* Hit at this line.  If we haven't shown the
                         * pre-context lines, we would need to show them.
-                        * When asked to do "count", this still show
-                        * the context which is nonsense, but the user
-                        * deserves to get that ;-).
                         */
                        if (opt->pre_context)
                                show_pre_context(opt, name, buf, bol, lno);
                        else if (opt->funcname)
                                show_funcname_line(opt, name, buf, bol, lno);
-                       if (!opt->count)
-                               show_line(opt, bol, eol, name, lno, ':');
+                       show_line(opt, bol, eol, name, lno, ':');
                        last_hit = lno;
                }
                else if (last_hit &&
@@ -937,6 +1083,7 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                output_sep(opt, ':');
                snprintf(buf, sizeof(buf), "%u\n", count);
                opt->output(opt, buf, strlen(buf));
+               return 1;
        }
        return !!last_hit;
 }