git-rebase.txt: Fix spelling
[gitweb.git] / grep.c
diff --git a/grep.c b/grep.c
index 704facf996657433f333a58381836e7e5df22bc6..8e1f7de7717da95e8954491f5205547f2091aa35 100644 (file)
--- a/grep.c
+++ b/grep.c
@@ -1,5 +1,6 @@
 #include "cache.h"
 #include "grep.h"
+#include "userdiff.h"
 #include "xdiff-interface.h"
 
 void append_header_grep_pattern(struct grep_opt *opt, enum grep_header_field field, const char *pat)
@@ -30,7 +31,19 @@ void append_grep_pattern(struct grep_opt *opt, const char *pat,
 
 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 {
-       int err = regcomp(&p->regexp, p->pattern, opt->regflags);
+       int err;
+
+       p->word_regexp = opt->word_regexp;
+       p->ignore_case = opt->ignore_case;
+
+       if (opt->fixed)
+               p->fixed = 1;
+       if (opt->regflags & REG_ICASE)
+               p->fixed = 0;
+       if (p->fixed)
+               return;
+
+       err = regcomp(&p->regexp, p->pattern, opt->regflags);
        if (err) {
                char errbuf[1024];
                char where[1024];
@@ -161,8 +174,7 @@ void compile_grep_patterns(struct grep_opt *opt)
                case GREP_PATTERN: /* atom */
                case GREP_PATTERN_HEAD:
                case GREP_PATTERN_BODY:
-                       if (!opt->fixed)
-                               compile_regexp(p, opt);
+                       compile_regexp(p, opt);
                        break;
                default:
                        opt->extended = 1;
@@ -177,7 +189,8 @@ void compile_grep_patterns(struct grep_opt *opt)
         * A classic recursive descent parser would do.
         */
        p = opt->pattern_list;
-       opt->pattern_expression = compile_pattern_expr(&p);
+       if (p)
+               opt->pattern_expression = compile_pattern_expr(&p);
        if (p)
                die("incomplete pattern expression: %s", p->pattern);
 }
@@ -238,26 +251,20 @@ static int word_char(char ch)
        return isalnum(ch) || ch == '_';
 }
 
-static void show_line(struct grep_opt *opt, const char *bol, const char *eol,
-                     const char *name, unsigned lno, char sign)
-{
-       if (opt->null_following_name)
-               sign = '\0';
-       if (opt->pathname)
-               printf("%s%c", name, sign);
-       if (opt->linenum)
-               printf("%d%c", lno, sign);
-       printf("%.*s\n", (int)(eol-bol), bol);
-}
-
 static void show_name(struct grep_opt *opt, const char *name)
 {
        printf("%s%c", name, opt->null_following_name ? '\0' : '\n');
 }
 
-static int fixmatch(const char *pattern, char *line, regmatch_t *match)
+
+static int fixmatch(const char *pattern, char *line, int ignore_case, regmatch_t *match)
 {
-       char *hit = strstr(line, pattern);
+       char *hit;
+       if (ignore_case)
+               hit = strcasestr(line, pattern);
+       else
+               hit = strstr(line, pattern);
+
        if (!hit) {
                match->rm_so = match->rm_eo = -1;
                return REG_NOMATCH;
@@ -293,12 +300,13 @@ static struct {
        { "committer ", 10 },
 };
 
-static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol, char *eol, enum grep_context ctx)
+static int match_one_pattern(struct grep_pat *p, char *bol, char *eol,
+                            enum grep_context ctx,
+                            regmatch_t *pmatch, int eflags)
 {
        int hit = 0;
-       int at_true_bol = 1;
        int saved_ch = 0;
-       regmatch_t pmatch[10];
+       const char *start = bol;
 
        if ((p->token != GREP_PATTERN) &&
            ((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
@@ -317,18 +325,14 @@ static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol
        }
 
  again:
-       if (!opt->fixed) {
-               regex_t *exp = &p->regexp;
-               hit = !regexec(exp, bol, ARRAY_SIZE(pmatch),
-                              pmatch, 0);
-       }
-       else {
-               hit = !fixmatch(p->pattern, bol, pmatch);
-       }
+       if (p->fixed)
+               hit = !fixmatch(p->pattern, bol, p->ignore_case, pmatch);
+       else
+               hit = !regexec(&p->regexp, bol, 1, pmatch, eflags);
 
-       if (hit && opt->word_regexp) {
+       if (hit && p->word_regexp) {
                if ((pmatch[0].rm_so < 0) ||
-                   (eol - bol) <= pmatch[0].rm_so ||
+                   (eol - bol) < pmatch[0].rm_so ||
                    (pmatch[0].rm_eo < 0) ||
                    (eol - bol) < pmatch[0].rm_eo)
                        die("regexp returned nonsense");
@@ -339,7 +343,7 @@ static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol
                 * either end of the line, or at word boundary
                 * (i.e. the next char must not be a word char).
                 */
-               if ( ((pmatch[0].rm_so == 0 && at_true_bol) ||
+               if ( ((pmatch[0].rm_so == 0) ||
                      !word_char(bol[pmatch[0].rm_so-1])) &&
                     ((pmatch[0].rm_eo == (eol-bol)) ||
                      !word_char(bol[pmatch[0].rm_eo])) )
@@ -347,59 +351,66 @@ static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol
                else
                        hit = 0;
 
+               /* Words consist of at least one character. */
+               if (pmatch->rm_so == pmatch->rm_eo)
+                       hit = 0;
+
                if (!hit && pmatch[0].rm_so + bol + 1 < eol) {
                        /* There could be more than one match on the
                         * line, and the first match might not be
                         * strict word match.  But later ones could be!
+                        * Forward to the next possible start, i.e. the
+                        * next position following a non-word char.
                         */
                        bol = pmatch[0].rm_so + bol + 1;
-                       at_true_bol = 0;
-                       goto again;
+                       while (word_char(bol[-1]) && bol < eol)
+                               bol++;
+                       eflags |= REG_NOTBOL;
+                       if (bol < eol)
+                               goto again;
                }
        }
        if (p->token == GREP_PATTERN_HEAD && saved_ch)
                *eol = saved_ch;
+       if (hit) {
+               pmatch[0].rm_so += bol - start;
+               pmatch[0].rm_eo += bol - start;
+       }
        return hit;
 }
 
-static int match_expr_eval(struct grep_opt *o,
-                          struct grep_expr *x,
-                          char *bol, char *eol,
-                          enum grep_context ctx,
-                          int collect_hits)
+static int match_expr_eval(struct grep_expr *x, char *bol, char *eol,
+                          enum grep_context ctx, int collect_hits)
 {
        int h = 0;
+       regmatch_t match;
 
        if (!x)
                die("Not a valid grep expression");
        switch (x->node) {
        case GREP_NODE_ATOM:
-               h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
+               h = match_one_pattern(x->u.atom, bol, eol, ctx, &match, 0);
                break;
        case GREP_NODE_NOT:
-               h = !match_expr_eval(o, x->u.unary, bol, eol, ctx, 0);
+               h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
                break;
        case GREP_NODE_AND:
-               if (!collect_hits)
-                       return (match_expr_eval(o, x->u.binary.left,
-                                               bol, eol, ctx, 0) &&
-                               match_expr_eval(o, x->u.binary.right,
-                                               bol, eol, ctx, 0));
-               h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
-               h &= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 0);
+               if (!match_expr_eval(x->u.binary.left, bol, eol, ctx, 0))
+                       return 0;
+               h = match_expr_eval(x->u.binary.right, bol, eol, ctx, 0);
                break;
        case GREP_NODE_OR:
                if (!collect_hits)
-                       return (match_expr_eval(o, x->u.binary.left,
+                       return (match_expr_eval(x->u.binary.left,
                                                bol, eol, ctx, 0) ||
-                               match_expr_eval(o, x->u.binary.right,
+                               match_expr_eval(x->u.binary.right,
                                                bol, eol, ctx, 0));
-               h = match_expr_eval(o, x->u.binary.left, bol, eol, ctx, 0);
+               h = match_expr_eval(x->u.binary.left, bol, eol, ctx, 0);
                x->u.binary.left->hit |= h;
-               h |= match_expr_eval(o, x->u.binary.right, bol, eol, ctx, 1);
+               h |= match_expr_eval(x->u.binary.right, bol, eol, ctx, 1);
                break;
        default:
-               die("Unexpected node type (internal error) %d\n", x->node);
+               die("Unexpected node type (internal error) %d", x->node);
        }
        if (collect_hits)
                x->hit |= h;
@@ -410,40 +421,266 @@ static int match_expr(struct grep_opt *opt, char *bol, char *eol,
                      enum grep_context ctx, int collect_hits)
 {
        struct grep_expr *x = opt->pattern_expression;
-       return match_expr_eval(opt, x, bol, eol, ctx, collect_hits);
+       return match_expr_eval(x, bol, eol, ctx, collect_hits);
 }
 
 static int match_line(struct grep_opt *opt, char *bol, char *eol,
                      enum grep_context ctx, int collect_hits)
 {
        struct grep_pat *p;
+       regmatch_t match;
+
        if (opt->extended)
                return match_expr(opt, bol, eol, ctx, collect_hits);
 
        /* we do not call with collect_hits without being extended */
        for (p = opt->pattern_list; p; p = p->next) {
-               if (match_one_pattern(opt, p, bol, eol, ctx))
+               if (match_one_pattern(p, bol, eol, ctx, &match, 0))
                        return 1;
        }
        return 0;
 }
 
+static int match_next_pattern(struct grep_pat *p, char *bol, char *eol,
+                             enum grep_context ctx,
+                             regmatch_t *pmatch, int eflags)
+{
+       regmatch_t match;
+
+       if (!match_one_pattern(p, bol, eol, ctx, &match, eflags))
+               return 0;
+       if (match.rm_so < 0 || match.rm_eo < 0)
+               return 0;
+       if (pmatch->rm_so >= 0 && pmatch->rm_eo >= 0) {
+               if (match.rm_so > pmatch->rm_so)
+                       return 1;
+               if (match.rm_so == pmatch->rm_so && match.rm_eo < pmatch->rm_eo)
+                       return 1;
+       }
+       pmatch->rm_so = match.rm_so;
+       pmatch->rm_eo = match.rm_eo;
+       return 1;
+}
+
+static int next_match(struct grep_opt *opt, char *bol, char *eol,
+                     enum grep_context ctx, regmatch_t *pmatch, int eflags)
+{
+       struct grep_pat *p;
+       int hit = 0;
+
+       pmatch->rm_so = pmatch->rm_eo = -1;
+       if (bol < eol) {
+               for (p = opt->pattern_list; p; p = p->next) {
+                       switch (p->token) {
+                       case GREP_PATTERN: /* atom */
+                       case GREP_PATTERN_HEAD:
+                       case GREP_PATTERN_BODY:
+                               hit |= match_next_pattern(p, bol, eol, ctx,
+                                                         pmatch, eflags);
+                               break;
+                       default:
+                               break;
+                       }
+               }
+       }
+       return hit;
+}
+
+static void show_line(struct grep_opt *opt, char *bol, char *eol,
+                     const char *name, unsigned lno, char sign)
+{
+       int rest = eol - bol;
+
+       if (opt->pre_context || opt->post_context) {
+               if (opt->last_shown == 0) {
+                       if (opt->show_hunk_mark)
+                               fputs("--\n", stdout);
+                       else
+                               opt->show_hunk_mark = 1;
+               } else if (lno > opt->last_shown + 1)
+                       fputs("--\n", stdout);
+       }
+       opt->last_shown = lno;
+
+       if (opt->null_following_name)
+               sign = '\0';
+       if (opt->pathname)
+               printf("%s%c", name, sign);
+       if (opt->linenum)
+               printf("%d%c", lno, sign);
+       if (opt->color) {
+               regmatch_t match;
+               enum grep_context ctx = GREP_CONTEXT_BODY;
+               int ch = *eol;
+               int eflags = 0;
+
+               *eol = '\0';
+               while (next_match(opt, bol, eol, ctx, &match, eflags)) {
+                       if (match.rm_so == match.rm_eo)
+                               break;
+                       printf("%.*s%s%.*s%s",
+                              (int)match.rm_so, bol,
+                              opt->color_match,
+                              (int)(match.rm_eo - match.rm_so), bol + match.rm_so,
+                              GIT_COLOR_RESET);
+                       bol += match.rm_eo;
+                       rest -= match.rm_eo;
+                       eflags = REG_NOTBOL;
+               }
+               *eol = ch;
+       }
+       printf("%.*s\n", rest, bol);
+}
+
+static int match_funcname(struct grep_opt *opt, char *bol, char *eol)
+{
+       xdemitconf_t *xecfg = opt->priv;
+       if (xecfg && xecfg->find_func) {
+               char buf[1];
+               return xecfg->find_func(bol, eol - bol, buf, 1,
+                                       xecfg->find_func_priv) >= 0;
+       }
+
+       if (bol == eol)
+               return 0;
+       if (isalpha(*bol) || *bol == '_' || *bol == '$')
+               return 1;
+       return 0;
+}
+
+static void show_funcname_line(struct grep_opt *opt, const char *name,
+                              char *buf, char *bol, unsigned lno)
+{
+       while (bol > buf) {
+               char *eol = --bol;
+
+               while (bol > buf && bol[-1] != '\n')
+                       bol--;
+               lno--;
+
+               if (lno <= opt->last_shown)
+                       break;
+
+               if (match_funcname(opt, bol, eol)) {
+                       show_line(opt, bol, eol, name, lno, '=');
+                       break;
+               }
+       }
+}
+
+static void show_pre_context(struct grep_opt *opt, const char *name, char *buf,
+                            char *bol, unsigned lno)
+{
+       unsigned cur = lno, from = 1, funcname_lno = 0;
+       int funcname_needed = opt->funcname;
+
+       if (opt->pre_context < lno)
+               from = lno - opt->pre_context;
+       if (from <= opt->last_shown)
+               from = opt->last_shown + 1;
+
+       /* Rewind. */
+       while (bol > buf && cur > from) {
+               char *eol = --bol;
+
+               while (bol > buf && bol[-1] != '\n')
+                       bol--;
+               cur--;
+               if (funcname_needed && match_funcname(opt, bol, eol)) {
+                       funcname_lno = cur;
+                       funcname_needed = 0;
+               }
+       }
+
+       /* We need to look even further back to find a function signature. */
+       if (opt->funcname && funcname_needed)
+               show_funcname_line(opt, name, buf, bol, cur);
+
+       /* Back forward. */
+       while (cur < lno) {
+               char *eol = bol, sign = (cur == funcname_lno) ? '=' : '-';
+
+               while (*eol != '\n')
+                       eol++;
+               show_line(opt, bol, eol, name, cur, sign);
+               bol = eol + 1;
+               cur++;
+       }
+}
+
+static int should_lookahead(struct grep_opt *opt)
+{
+       struct grep_pat *p;
+
+       if (opt->extended)
+               return 0; /* punt for too complex stuff */
+       if (opt->invert)
+               return 0;
+       for (p = opt->pattern_list; p; p = p->next) {
+               if (p->token != GREP_PATTERN)
+                       return 0; /* punt for "header only" and stuff */
+       }
+       return 1;
+}
+
+static int look_ahead(struct grep_opt *opt,
+                     unsigned long *left_p,
+                     unsigned *lno_p,
+                     char **bol_p)
+{
+       unsigned lno = *lno_p;
+       char *bol = *bol_p;
+       struct grep_pat *p;
+       char *sp, *last_bol;
+       regoff_t earliest = -1;
+
+       for (p = opt->pattern_list; p; p = p->next) {
+               int hit;
+               regmatch_t m;
+
+               if (p->fixed)
+                       hit = !fixmatch(p->pattern, bol, p->ignore_case, &m);
+               else
+                       hit = !regexec(&p->regexp, bol, 1, &m, 0);
+               if (!hit || m.rm_so < 0 || m.rm_eo < 0)
+                       continue;
+               if (earliest < 0 || m.rm_so < earliest)
+                       earliest = m.rm_so;
+       }
+
+       if (earliest < 0) {
+               *bol_p = bol + *left_p;
+               *left_p = 0;
+               return 1;
+       }
+       for (sp = bol + earliest; bol < sp && sp[-1] != '\n'; sp--)
+               ; /* find the beginning of the line */
+       last_bol = sp;
+
+       for (sp = bol; sp < last_bol; sp++) {
+               if (*sp == '\n')
+                       lno++;
+       }
+       *left_p -= last_bol - bol;
+       *bol_p = last_bol;
+       *lno_p = lno;
+       return 0;
+}
+
 static int grep_buffer_1(struct grep_opt *opt, const char *name,
                         char *buf, unsigned long size, int collect_hits)
 {
        char *bol = buf;
        unsigned long left = size;
        unsigned lno = 1;
-       struct pre_context_line {
-               char *bol;
-               char *eol;
-       } *prev = NULL, *pcl;
        unsigned last_hit = 0;
-       unsigned last_shown = 0;
        int binary_match_only = 0;
-       const char *hunk_mark = "";
        unsigned count = 0;
+       int try_lookahead = 0;
        enum grep_context ctx = GREP_CONTEXT_HEAD;
+       xdemitconf_t xecfg;
+
+       opt->last_shown = 0;
 
        if (buffer_is_binary(buf, size)) {
                switch (opt->binary) {
@@ -458,15 +695,36 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                }
        }
 
-       if (opt->pre_context)
-               prev = xcalloc(opt->pre_context, sizeof(*prev));
-       if (opt->pre_context || opt->post_context)
-               hunk_mark = "--\n";
+       memset(&xecfg, 0, sizeof(xecfg));
+       if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
+           !opt->name_only && !binary_match_only && !collect_hits) {
+               struct userdiff_driver *drv = userdiff_find_by_path(name);
+               if (drv && drv->funcname.pattern) {
+                       const struct userdiff_funcname *pe = &drv->funcname;
+                       xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags);
+                       opt->priv = &xecfg;
+               }
+       }
+       try_lookahead = should_lookahead(opt);
 
        while (left) {
                char *eol, ch;
                int hit;
 
+               /*
+                * look_ahead() skips quicly 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.
+                * inside a post-context window, we will show the current
+                * line as a context around the previous hit when it
+                * doesn't hit.
+                */
+               if (try_lookahead
+                   && !(last_hit
+                        && lno <= last_hit + opt->post_context)
+                   && look_ahead(opt, &left, &lno, &bol))
+                       break;
                eol = end_of_line(bol, &left);
                ch = *eol;
                *eol = 0;
@@ -509,45 +767,20 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                         * the context which is nonsense, but the user
                         * deserves to get that ;-).
                         */
-                       if (opt->pre_context) {
-                               unsigned from;
-                               if (opt->pre_context < lno)
-                                       from = lno - opt->pre_context;
-                               else
-                                       from = 1;
-                               if (from <= last_shown)
-                                       from = last_shown + 1;
-                               if (last_shown && from != last_shown + 1)
-                                       fputs(hunk_mark, stdout);
-                               while (from < lno) {
-                                       pcl = &prev[lno-from-1];
-                                       show_line(opt, pcl->bol, pcl->eol,
-                                                 name, from, '-');
-                                       from++;
-                               }
-                               last_shown = lno-1;
-                       }
-                       if (last_shown && lno != last_shown + 1)
-                               fputs(hunk_mark, stdout);
+                       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, ':');
-                       last_shown = last_hit = lno;
+                       last_hit = lno;
                }
                else if (last_hit &&
                         lno <= last_hit + opt->post_context) {
                        /* If the last hit is within the post context,
                         * we need to show this line.
                         */
-                       if (last_shown && lno != last_shown + 1)
-                               fputs(hunk_mark, stdout);
                        show_line(opt, bol, eol, name, lno, '-');
-                       last_shown = lno;
-               }
-               if (opt->pre_context) {
-                       memmove(prev+1, prev,
-                               (opt->pre_context-1) * sizeof(*prev));
-                       prev->bol = bol;
-                       prev->eol = eol;
                }
 
        next_line:
@@ -558,7 +791,6 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                lno++;
        }
 
-       free(prev);
        if (collect_hits)
                return 0;
 
@@ -570,6 +802,9 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name,
                return 1;
        }
 
+       xdiff_clear_find_func(&xecfg);
+       opt->priv = NULL;
+
        /* NEEDSWORK:
         * The real "grep -c foo *.c" gives many "bar.c:0" lines,
         * which feels mostly useless but sometimes useful.  Maybe