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authorJunio C Hamano <junkio@cox.net>2006-09-17 23:02:52 (GMT)
committerJunio C Hamano <junkio@cox.net>2006-09-20 18:14:38 (GMT)
commit83b5d2f5b0c95fe102bc3d1cc2947abbdf5e5c5b (patch)
tree16348287b2cb6ebdba2e5068467b6b592b3ec3c7 /builtin-grep.c
parent62e27f273d66afa996cb7aee6cdb25fbedc053f6 (diff)
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builtin-grep: make pieces of it available as library.
This makes three functions and associated option structures from builtin-grep available from other parts of the system. * options to drive built-in grep engine is stored in struct grep_opt; * pattern strings and extended grep expressions are added to struct grep_opt with append_grep_pattern(); * when finished calling append_grep_pattern(), call compile_grep_patterns() to prepare for execution; * call grep_buffer() to find matches in the in-core buffer. This also adds an internal option "status_only" to grep_opt, which suppresses any output from grep_buffer(). Callers of the function as library can use it to check if there is a match without producing any output. Signed-off-by: Junio C Hamano <junkio@cox.net>
Diffstat (limited to 'builtin-grep.c')
-rw-r--r--builtin-grep.c522
1 files changed, 18 insertions, 504 deletions
diff --git a/builtin-grep.c b/builtin-grep.c
index ed87a55..6718788 100644
--- a/builtin-grep.c
+++ b/builtin-grep.c
@@ -11,6 +11,7 @@
#include "tree-walk.h"
#include "builtin.h"
#include <regex.h>
+#include "grep.h"
#include <fnmatch.h>
#include <sys/wait.h>
@@ -82,498 +83,6 @@ static int pathspec_matches(const char **paths, const char *name)
return 0;
}
-enum grep_pat_token {
- GREP_PATTERN,
- GREP_AND,
- GREP_OPEN_PAREN,
- GREP_CLOSE_PAREN,
- GREP_NOT,
- GREP_OR,
-};
-
-struct grep_pat {
- struct grep_pat *next;
- const char *origin;
- int no;
- enum grep_pat_token token;
- const char *pattern;
- regex_t regexp;
-};
-
-enum grep_expr_node {
- GREP_NODE_ATOM,
- GREP_NODE_NOT,
- GREP_NODE_AND,
- GREP_NODE_OR,
-};
-
-struct grep_expr {
- enum grep_expr_node node;
- union {
- struct grep_pat *atom;
- struct grep_expr *unary;
- struct {
- struct grep_expr *left;
- struct grep_expr *right;
- } binary;
- } u;
-};
-
-struct grep_opt {
- struct grep_pat *pattern_list;
- struct grep_pat **pattern_tail;
- struct grep_expr *pattern_expression;
- int prefix_length;
- regex_t regexp;
- unsigned linenum:1;
- unsigned invert:1;
- unsigned name_only:1;
- unsigned unmatch_name_only:1;
- unsigned count:1;
- unsigned word_regexp:1;
- unsigned fixed:1;
-#define GREP_BINARY_DEFAULT 0
-#define GREP_BINARY_NOMATCH 1
-#define GREP_BINARY_TEXT 2
- unsigned binary:2;
- unsigned extended:1;
- unsigned relative:1;
- unsigned pathname:1;
- int regflags;
- unsigned pre_context;
- unsigned post_context;
-};
-
-static void add_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_expr(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 */
- 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_expr(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);
-}
-
-static void compile_patterns(struct grep_opt *opt)
-{
- struct grep_pat *p;
-
- /* First compile regexps */
- for (p = opt->pattern_list; p; p = p->next) {
- if (p->token == GREP_PATTERN)
- compile_regexp(p, opt);
- else
- opt->extended = 1;
- }
-
- 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 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);
-}
-
-/*
- * NEEDSWORK: share code with diff.c
- */
-#define FIRST_FEW_BYTES 8000
-static int buffer_is_binary(const char *ptr, unsigned long size)
-{
- if (FIRST_FEW_BYTES < size)
- size = FIRST_FEW_BYTES;
- return !!memchr(ptr, 0, size);
-}
-
-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)
-{
- int hit = 0;
- int at_true_bol = 1;
- regmatch_t pmatch[10];
-
- 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 *opt,
- struct grep_expr *x,
- char *bol, char *eol)
-{
- switch (x->node) {
- case GREP_NODE_ATOM:
- return match_one_pattern(opt, x->u.atom, bol, eol);
- break;
- case GREP_NODE_NOT:
- return !match_expr_eval(opt, x->u.unary, bol, eol);
- case GREP_NODE_AND:
- return (match_expr_eval(opt, x->u.binary.left, bol, eol) &&
- match_expr_eval(opt, x->u.binary.right, bol, eol));
- case GREP_NODE_OR:
- return (match_expr_eval(opt, x->u.binary.left, bol, eol) ||
- match_expr_eval(opt, x->u.binary.right, bol, eol));
- }
- die("Unexpected node type (internal error) %d\n", x->node);
-}
-
-static int match_expr(struct grep_opt *opt, char *bol, char *eol)
-{
- struct grep_expr *x = opt->pattern_expression;
- return match_expr_eval(opt, x, bol, eol);
-}
-
-static int match_line(struct grep_opt *opt, char *bol, char *eol)
-{
- struct grep_pat *p;
- if (opt->extended)
- return match_expr(opt, bol, eol);
- for (p = opt->pattern_list; p; p = p->next) {
- if (match_one_pattern(opt, p, bol, eol))
- return 1;
- }
- return 0;
-}
-
-static int grep_buffer(struct grep_opt *opt, const char *name,
- char *buf, unsigned long size)
-{
- 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;
-
- 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 = 0;
-
- eol = end_of_line(bol, &left);
- ch = *eol;
- *eol = 0;
-
- hit = match_line(opt, bol, eol);
-
- /* "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 (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:
- *eol = ch;
- bol = eol + 1;
- if (!left)
- break;
- left--;
- lno++;
- }
-
- 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 int grep_sha1(struct grep_opt *opt, const unsigned char *sha1, const char *name, int tree_name_len)
{
unsigned long size;
@@ -1055,8 +564,9 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
/* ignore empty line like grep does */
if (!buf[0])
continue;
- add_pattern(&opt, xstrdup(buf), argv[1], ++lno,
- GREP_PATTERN);
+ append_grep_pattern(&opt, xstrdup(buf),
+ argv[1], ++lno,
+ GREP_PATTERN);
}
fclose(patterns);
argv++;
@@ -1064,27 +574,32 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
continue;
}
if (!strcmp("--not", arg)) {
- add_pattern(&opt, arg, "command line", 0, GREP_NOT);
+ append_grep_pattern(&opt, arg, "command line", 0,
+ GREP_NOT);
continue;
}
if (!strcmp("--and", arg)) {
- add_pattern(&opt, arg, "command line", 0, GREP_AND);
+ append_grep_pattern(&opt, arg, "command line", 0,
+ GREP_AND);
continue;
}
if (!strcmp("--or", arg))
continue; /* no-op */
if (!strcmp("(", arg)) {
- add_pattern(&opt, arg, "command line", 0, GREP_OPEN_PAREN);
+ append_grep_pattern(&opt, arg, "command line", 0,
+ GREP_OPEN_PAREN);
continue;
}
if (!strcmp(")", arg)) {
- add_pattern(&opt, arg, "command line", 0, GREP_CLOSE_PAREN);
+ append_grep_pattern(&opt, arg, "command line", 0,
+ GREP_CLOSE_PAREN);
continue;
}
if (!strcmp("-e", arg)) {
if (1 < argc) {
- add_pattern(&opt, argv[1], "-e option", 0,
- GREP_PATTERN);
+ append_grep_pattern(&opt, argv[1],
+ "-e option", 0,
+ GREP_PATTERN);
argv++;
argc--;
continue;
@@ -1106,8 +621,8 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
/* First unrecognized non-option token */
if (!opt.pattern_list) {
- add_pattern(&opt, arg, "command line", 0,
- GREP_PATTERN);
+ append_grep_pattern(&opt, arg, "command line", 0,
+ GREP_PATTERN);
break;
}
else {
@@ -1124,8 +639,7 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
die("no pattern given.");
if ((opt.regflags != REG_NEWLINE) && opt.fixed)
die("cannot mix --fixed-strings and regexp");
- if (!opt.fixed)
- compile_patterns(&opt);
+ compile_grep_patterns(&opt);
/* Check revs and then paths */
for (i = 1; i < argc; i++) {