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#include "cache.h"
#include "grep.h"
#include "xdiff-interface.h"
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 void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
{
int 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;
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 (!x)
return NULL;
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;
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:
if (!opt->fixed)
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;
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_line(struct grep_opt *opt, const char *bol, const char *eol,
const char *name, unsigned lno, char sign)
{
if (opt->pathname)
printf("%s%c", name, sign);
if (opt->linenum)
printf("%d%c", lno, sign);
printf("%.*s\n", (int)(eol-bol), bol);
}
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 match_one_pattern(struct grep_opt *opt, struct grep_pat *p, char *bol, char *eol, enum grep_context ctx)
{
int hit = 0;
int at_true_bol = 1;
regmatch_t pmatch[10];
if ((p->token != GREP_PATTERN) &&
((p->token == GREP_PATTERN_HEAD) != (ctx == GREP_CONTEXT_HEAD)))
return 0;
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 (hit && opt->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 && at_true_bol) ||
!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!
*/
bol = pmatch[0].rm_so + bol + 1;
at_true_bol = 0;
goto again;
}
}
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)
{
int h = 0;
switch (x->node) {
case GREP_NODE_ATOM:
h = match_one_pattern(o, x->u.atom, bol, eol, ctx);
break;
case GREP_NODE_NOT:
h = !match_expr_eval(o, 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);
break;
case GREP_NODE_OR:
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);
}
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(opt, 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;
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))
return 1;
}
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;
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) {
printf("%s\n", 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)
printf(hunk_mark);
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)
printf(hunk_mark);
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)
printf(hunk_mark);
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 */
printf("%s\n", 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:%u\n", name, 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);
}