git/grep.c
Junio C Hamano 07b838f087 Merge branch 'rs/threaded-grep-context'
* rs/threaded-grep-context:
  grep: enable threading for context line printing

Conflicts:
	grep.c
2010-04-03 12:28:39 -07:00

990 lines
22 KiB
C

#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)
{
struct grep_pat *p = xcalloc(1, sizeof(*p));
p->pattern = pat;
p->origin = "header";
p->no = 0;
p->token = GREP_PATTERN_HEAD;
p->field = field;
*opt->header_tail = p;
opt->header_tail = &p->next;
p->next = NULL;
}
void append_grep_pattern(struct grep_opt *opt, const char *pat,
const char *origin, int no, enum grep_pat_token t)
{
struct grep_pat *p = xcalloc(1, sizeof(*p));
p->pattern = pat;
p->origin = origin;
p->no = no;
p->token = t;
*opt->pattern_tail = p;
opt->pattern_tail = &p->next;
p->next = NULL;
}
struct grep_opt *grep_opt_dup(const struct grep_opt *opt)
{
struct grep_pat *pat;
struct grep_opt *ret = xmalloc(sizeof(struct grep_opt));
*ret = *opt;
ret->pattern_list = NULL;
ret->pattern_tail = &ret->pattern_list;
for(pat = opt->pattern_list; pat != NULL; pat = pat->next)
{
if(pat->token == GREP_PATTERN_HEAD)
append_header_grep_pattern(ret, pat->field,
pat->pattern);
else
append_grep_pattern(ret, pat->pattern, pat->origin,
pat->no, pat->token);
}
return ret;
}
static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
{
int err;
p->word_regexp = opt->word_regexp;
p->ignore_case = opt->ignore_case;
p->fixed = opt->fixed;
if (p->fixed)
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);
}
}
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;
struct grep_expr *x;
p = *list;
if (!p)
return NULL;
switch (p->token) {
case GREP_PATTERN: /* atom */
case GREP_PATTERN_HEAD:
case GREP_PATTERN_BODY:
x = xcalloc(1, sizeof (struct grep_expr));
x->node = GREP_NODE_ATOM;
x->u.atom = p;
*list = p->next;
return x;
case GREP_OPEN_PAREN:
*list = p->next;
x = compile_pattern_or(list);
if (!*list || (*list)->token != GREP_CLOSE_PAREN)
die("unmatched parenthesis");
*list = (*list)->next;
return x;
default:
return NULL;
}
}
static struct grep_expr *compile_pattern_not(struct grep_pat **list)
{
struct grep_pat *p;
struct grep_expr *x;
p = *list;
if (!p)
return NULL;
switch (p->token) {
case GREP_NOT:
if (!p->next)
die("--not not followed by pattern expression");
*list = p->next;
x = xcalloc(1, sizeof (struct grep_expr));
x->node = GREP_NODE_NOT;
x->u.unary = compile_pattern_not(list);
if (!x->u.unary)
die("--not followed by non pattern expression");
return x;
default:
return compile_pattern_atom(list);
}
}
static struct grep_expr *compile_pattern_and(struct grep_pat **list)
{
struct grep_pat *p;
struct grep_expr *x, *y, *z;
x = compile_pattern_not(list);
p = *list;
if (p && p->token == GREP_AND) {
if (!p->next)
die("--and not followed by pattern expression");
*list = p->next;
y = compile_pattern_and(list);
if (!y)
die("--and not followed by pattern expression");
z = xcalloc(1, sizeof (struct grep_expr));
z->node = GREP_NODE_AND;
z->u.binary.left = x;
z->u.binary.right = y;
return z;
}
return x;
}
static struct grep_expr *compile_pattern_or(struct grep_pat **list)
{
struct grep_pat *p;
struct grep_expr *x, *y, *z;
x = compile_pattern_and(list);
p = *list;
if (x && p && p->token != GREP_CLOSE_PAREN) {
y = compile_pattern_or(list);
if (!y)
die("not a pattern expression %s", p->pattern);
z = xcalloc(1, sizeof (struct grep_expr));
z->node = GREP_NODE_OR;
z->u.binary.left = x;
z->u.binary.right = y;
return z;
}
return x;
}
static struct grep_expr *compile_pattern_expr(struct grep_pat **list)
{
return compile_pattern_or(list);
}
void compile_grep_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;
}
}
}
for (p = opt->pattern_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;
}
}
if (opt->all_match || header_expr)
opt->extended = 1;
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);
if (p)
die("incomplete pattern expression: %s", p->pattern);
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 {
opt->pattern_expression = header_expr;
}
opt->all_match = 1;
}
static void free_pattern_expr(struct grep_expr *x)
{
switch (x->node) {
case GREP_NODE_ATOM:
break;
case GREP_NODE_NOT:
free_pattern_expr(x->u.unary);
break;
case GREP_NODE_AND:
case GREP_NODE_OR:
free_pattern_expr(x->u.binary.left);
free_pattern_expr(x->u.binary.right);
break;
}
free(x);
}
void free_grep_patterns(struct grep_opt *opt)
{
struct grep_pat *p, *n;
for (p = opt->pattern_list; p; p = n) {
n = p->next;
switch (p->token) {
case GREP_PATTERN: /* atom */
case GREP_PATTERN_HEAD:
case GREP_PATTERN_BODY:
regfree(&p->regexp);
break;
default:
break;
}
free(p);
}
if (!opt->extended)
return;
free_pattern_expr(opt->pattern_expression);
}
static char *end_of_line(char *cp, unsigned long *left)
{
unsigned long l = *left;
while (l && *cp != '\n') {
l--;
cp++;
}
*left = l;
return cp;
}
static int word_char(char ch)
{
return isalnum(ch) || ch == '_';
}
static void output_color(struct grep_opt *opt, const void *data, size_t size,
const char *color)
{
if (opt->color && color && color[0]) {
opt->output(opt, color, strlen(color));
opt->output(opt, data, size);
opt->output(opt, GIT_COLOR_RESET, strlen(GIT_COLOR_RESET));
} else
opt->output(opt, data, size);
}
static void output_sep(struct grep_opt *opt, char sign)
{
if (opt->null_following_name)
opt->output(opt, "\0", 1);
else
output_color(opt, &sign, 1, opt->color_sep);
}
static void show_name(struct grep_opt *opt, const char *name)
{
output_color(opt, name, strlen(name), opt->color_filename);
opt->output(opt, opt->null_following_name ? "\0" : "\n", 1);
}
static int fixmatch(const char *pattern, char *line, int ignore_case, regmatch_t *match)
{
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;
}
else {
match->rm_so = hit - line;
match->rm_eo = match->rm_so + strlen(pattern);
return 0;
}
}
static int strip_timestamp(char *bol, char **eol_p)
{
char *eol = *eol_p;
int ch;
while (bol < --eol) {
if (*eol != '>')
continue;
*eol_p = ++eol;
ch = *eol;
*eol = '\0';
return ch;
}
return 0;
}
static struct {
const char *field;
size_t len;
} header_field[] = {
{ "author ", 7 },
{ "committer ", 10 },
};
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 saved_ch = 0;
const char *start = bol;
if ((p->token != GREP_PATTERN) &&
((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
return 0;
if (p->token == GREP_PATTERN_HEAD) {
const char *field;
size_t len;
assert(p->field < ARRAY_SIZE(header_field));
field = header_field[p->field].field;
len = header_field[p->field].len;
if (strncmp(bol, field, len))
return 0;
bol += len;
saved_ch = strip_timestamp(bol, &eol);
}
again:
if (p->fixed)
hit = !fixmatch(p->pattern, bol, p->ignore_case, pmatch);
else
hit = !regexec(&p->regexp, bol, 1, pmatch, eflags);
if (hit && p->word_regexp) {
if ((pmatch[0].rm_so < 0) ||
(eol - bol) < pmatch[0].rm_so ||
(pmatch[0].rm_eo < 0) ||
(eol - bol) < pmatch[0].rm_eo)
die("regexp returned nonsense");
/* Match beginning must be either beginning of the
* line, or at word boundary (i.e. the last char must
* not be a word char). Similarly, match end must be
* 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) ||
!word_char(bol[pmatch[0].rm_so-1])) &&
((pmatch[0].rm_eo == (eol-bol)) ||
!word_char(bol[pmatch[0].rm_eo])) )
;
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;
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_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(x->u.atom, bol, eol, ctx, &match, 0);
break;
case GREP_NODE_NOT:
h = !match_expr_eval(x->u.unary, bol, eol, ctx, 0);
break;
case GREP_NODE_AND:
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(x->u.binary.left,
bol, eol, ctx, 0) ||
match_expr_eval(x->u.binary.right,
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(x->u.binary.right, bol, eol, ctx, 1);
break;
default:
die("Unexpected node type (internal error) %d", 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, int collect_hits)
{
struct grep_expr *x = opt->pattern_expression;
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(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;
char *line_color = NULL;
if (opt->pre_context || opt->post_context) {
if (opt->last_shown == 0) {
if (opt->show_hunk_mark) {
output_color(opt, "--", 2, opt->color_sep);
opt->output(opt, "\n", 1);
}
} else if (lno > opt->last_shown + 1) {
output_color(opt, "--", 2, opt->color_sep);
opt->output(opt, "\n", 1);
}
}
opt->last_shown = lno;
if (opt->pathname) {
output_color(opt, name, strlen(name), opt->color_filename);
output_sep(opt, sign);
}
if (opt->linenum) {
char buf[32];
snprintf(buf, sizeof(buf), "%d", lno);
output_color(opt, buf, strlen(buf), opt->color_lineno);
output_sep(opt, sign);
}
if (opt->color) {
regmatch_t match;
enum grep_context ctx = GREP_CONTEXT_BODY;
int ch = *eol;
int eflags = 0;
if (sign == ':')
line_color = opt->color_selected;
else if (sign == '-')
line_color = opt->color_context;
else if (sign == '=')
line_color = opt->color_function;
*eol = '\0';
while (next_match(opt, bol, eol, ctx, &match, eflags)) {
if (match.rm_so == match.rm_eo)
break;
output_color(opt, bol, match.rm_so, line_color);
output_color(opt, bol + match.rm_so,
match.rm_eo - match.rm_so,
opt->color_match);
bol += match.rm_eo;
rest -= match.rm_eo;
eflags = REG_NOTBOL;
}
*eol = ch;
}
output_color(opt, bol, rest, line_color);
opt->output(opt, "\n", 1);
}
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 {
#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
}
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;
}
int grep_threads_ok(const struct grep_opt *opt)
{
/* If this condition is true, then we may use the attribute
* machinery in grep_buffer_1. The attribute code is not
* thread safe, so we disable the use of threads.
*/
if (opt->funcname && !opt->unmatch_name_only && !opt->status_only &&
!opt->name_only)
return 0;
return 1;
}
static void std_output(struct grep_opt *opt, const void *buf, size_t size)
{
fwrite(buf, size, 1, stdout);
}
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;
unsigned last_hit = 0;
int binary_match_only = 0;
unsigned count = 0;
int try_lookahead = 0;
enum grep_context ctx = GREP_CONTEXT_HEAD;
xdemitconf_t xecfg;
if (!opt->output)
opt->output = std_output;
if (opt->last_shown && (opt->pre_context || opt->post_context) &&
opt->output == std_output)
opt->show_hunk_mark = 1;
opt->last_shown = 0;
if (buffer_is_binary(buf, size)) {
switch (opt->binary) {
case GREP_BINARY_DEFAULT:
binary_match_only = 1;
break;
case GREP_BINARY_NOMATCH:
return 0; /* Assume unmatch */
break;
default:
break;
}
}
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;
if ((ctx == GREP_CONTEXT_HEAD) && (eol == bol))
ctx = GREP_CONTEXT_BODY;
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.
*/
if (opt->invert)
hit = !hit;
if (opt->unmatch_name_only) {
if (hit)
return 0;
goto next_line;
}
if (hit) {
count++;
if (opt->status_only)
return 1;
if (binary_match_only) {
opt->output(opt, "Binary file ", 12);
output_color(opt, name, strlen(name),
opt->color_filename);
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, ':');
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.
*/
show_line(opt, bol, eol, name, lno, '-');
}
next_line:
bol = eol + 1;
if (!left)
break;
left--;
lno++;
}
if (collect_hits)
return 0;
if (opt->status_only)
return 0;
if (opt->unmatch_name_only) {
/* We did not see any hit, so we want to show this */
show_name(opt, 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
* make it another option? For now suppress them.
*/
if (opt->count && count) {
char buf[32];
output_color(opt, name, strlen(name), opt->color_filename);
output_sep(opt, ':');
snprintf(buf, sizeof(buf), "%u\n", count);
opt->output(opt, buf, strlen(buf));
}
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);
}