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-rw-r--r--grep.c114
1 files changed, 96 insertions, 18 deletions
diff --git a/grep.c b/grep.c
index c411ddd4d..0fc078ec0 100644
--- a/grep.c
+++ b/grep.c
@@ -34,7 +34,7 @@ static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
}
}
-static struct grep_expr *compile_pattern_expr(struct grep_pat **);
+static struct grep_expr *compile_pattern_or(struct grep_pat **);
static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
{
struct grep_pat *p;
@@ -52,7 +52,7 @@ static struct grep_expr *compile_pattern_atom(struct grep_pat **list)
return x;
case GREP_OPEN_PAREN:
*list = p->next;
- x = compile_pattern_expr(list);
+ x = compile_pattern_or(list);
if (!x)
return NULL;
if (!*list || (*list)->token != GREP_CLOSE_PAREN)
@@ -138,6 +138,9 @@ void compile_grep_patterns(struct grep_opt *opt)
{
struct grep_pat *p;
+ if (opt->all_match)
+ opt->extended = 1;
+
for (p = opt->pattern_list; p; p = p->next) {
switch (p->token) {
case GREP_PATTERN: /* atom */
@@ -309,40 +312,63 @@ static int match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol
return hit;
}
-static int match_expr_eval(struct grep_opt *opt,
+static int match_expr_eval(struct grep_opt *o,
struct grep_expr *x,
char *bol, char *eol,
- enum grep_context ctx)
+ enum grep_context ctx,
+ int collect_hits)
{
+ int h = 0;
+
switch (x->node) {
case GREP_NODE_ATOM:
- return match_one_pattern(opt, x->u.atom, bol, eol, ctx);
+ h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
break;
case GREP_NODE_NOT:
- return !match_expr_eval(opt, x->u.unary, bol, eol, ctx);
+ h = !match_expr_eval(o, x->u.unary, bol, eol, ctx, 0);
+ break;
case GREP_NODE_AND:
- return (match_expr_eval(opt, x->u.binary.left, bol, eol, ctx) &&
- match_expr_eval(opt, x->u.binary.right, bol, eol, ctx));
+ 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);
+ break;
case GREP_NODE_OR:
- return (match_expr_eval(opt, x->u.binary.left, bol, eol, ctx) ||
- match_expr_eval(opt, x->u.binary.right, bol, eol, ctx));
+ 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);
+ x->u.binary.left->hit |= h;
+ h |= match_expr_eval(o, 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\n", x->node);
+ if (collect_hits)
+ x->hit |= h;
+ return h;
}
static int match_expr(struct grep_opt *opt, char *bol, char *eol,
- enum grep_context ctx)
+ enum grep_context ctx, int collect_hits)
{
struct grep_expr *x = opt->pattern_expression;
- return match_expr_eval(opt, x, bol, eol, ctx);
+ return match_expr_eval(opt, x, bol, eol, ctx, collect_hits);
}
static int match_line(struct grep_opt *opt, char *bol, char *eol,
- enum grep_context ctx)
+ enum grep_context ctx, int collect_hits)
{
struct grep_pat *p;
if (opt->extended)
- return match_expr(opt, bol, eol, ctx);
+ 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))
return 1;
@@ -350,7 +376,8 @@ static int match_line(struct grep_opt *opt, char *bol, char *eol,
return 0;
}
-int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
+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;
@@ -386,7 +413,7 @@ int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long
while (left) {
char *eol, ch;
- int hit = 0;
+ int hit;
eol = end_of_line(bol, &left);
ch = *eol;
@@ -395,9 +422,12 @@ int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long
if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
ctx = GREP_CONTEXT_BODY;
- hit = match_line(opt, bol, eol, ctx);
+ hit = match_line(opt, bol, eol, ctx, collect_hits);
*eol = ch;
+ if (collect_hits)
+ goto next_line;
+
/* "grep -v -e foo -e bla" should list lines
* that do not have either, so inversion should
* be done outside.
@@ -477,6 +507,8 @@ int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long
}
free(prev);
+ if (collect_hits)
+ return 0;
if (opt->status_only)
return 0;
@@ -496,3 +528,49 @@ int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long
return !!last_hit;
}
+static void clr_hit_marker(struct grep_expr *x)
+{
+ /* All-hit markers are meaningful only at the very top level
+ * OR node.
+ */
+ while (1) {
+ x->hit = 0;
+ if (x->node != GREP_NODE_OR)
+ return;
+ x->u.binary.left->hit = 0;
+ x = x->u.binary.right;
+ }
+}
+
+static int chk_hit_marker(struct grep_expr *x)
+{
+ /* Top level nodes have hit markers. See if they all are hits */
+ while (1) {
+ if (x->node != GREP_NODE_OR)
+ return x->hit;
+ if (!x->u.binary.left->hit)
+ return 0;
+ x = x->u.binary.right;
+ }
+}
+
+int grep_buffer(struct grep_opt *opt, const char *name, char *buf, unsigned long size)
+{
+ /*
+ * we do not have to do the two-pass grep when we do not check
+ * buffer-wide "all-match".
+ */
+ if (!opt->all_match)
+ return grep_buffer_1(opt, name, buf, size, 0);
+
+ /* Otherwise the toplevel "or" terms hit a bit differently.
+ * We first clear hit markers from them.
+ */
+ clr_hit_marker(opt->pattern_expression);
+ grep_buffer_1(opt, name, buf, size, 1);
+
+ if (!chk_hit_marker(opt->pattern_expression))
+ return 0;
+
+ return grep_buffer_1(opt, name, buf, size, 0);
+}