git/grep.c
René Scharfe e701fadb9e grep: fix word-regexp colouring
As noticed by Dmitry Gryazin: When a pattern is found but it doesn't
start and end at word boundaries, bol is forwarded to after the match and
the pattern is searched again.  When a pattern is finally found between
word boundaries, the match offsets are off by the number of characters
that have been skipped.

This patch corrects the offsets to be relative to the value of bol as
passed to match_one_pattern() by its caller.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-05-20 18:49:20 -07:00

715 lines
16 KiB
C

#include "cache.h"
#include "grep.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->pattern_tail = p;
opt->pattern_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;
}
static int is_fixed(const char *s)
{
while (*s && !is_regex_special(*s))
s++;
return !*s;
}
static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
{
int err;
p->word_regexp = opt->word_regexp;
if (opt->fixed || is_fixed(p->pattern))
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];
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;
if (opt->all_match)
opt->extended = 1;
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->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);
}
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 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)
{
char *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, 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;
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++;
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;
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)) {
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 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;
enum grep_context ctx = GREP_CONTEXT_HEAD;
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;
}
}
if (opt->pre_context)
prev = xcalloc(opt->pre_context, sizeof(*prev));
if (opt->pre_context || opt->post_context)
hunk_mark = "--\n";
while (left) {
char *eol, ch;
int hit;
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) {
printf("Binary file %s matches\n", name);
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) {
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->count)
show_line(opt, bol, eol, name, lno, ':');
last_shown = 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:
bol = eol + 1;
if (!left)
break;
left--;
lno++;
}
free(prev);
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;
}
/* 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)
printf("%s%c%u\n", name,
opt->null_following_name ? '\0' : ':', count);
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);
}