diffcore-pickaxe.c - jrn/git - Git at Google

 /*
  * Copyright (C) 2005 Junio C Hamano
  * Copyright (C) 2010 Google Inc.
  */
 #include "git-compat-util.h"
 #include "diff.h"
 #include "diffcore.h"
 #include "xdiff-interface.h"
 #include "kwset.h"
 #include "oidset.h"
 #include "pretty.h"
 #include "quote.h"

 typedef int (*pickaxe_fn)(mmfile_t *one, mmfile_t *two,
 			  struct diff_options *o,
 			  regex_t *regexp, kwset_t kws);

 struct diffgrep_cb {
 	regex_t *regexp;
 	int hit;
 };

 static int diffgrep_consume(void *priv, char *line, unsigned long len)
 {
 	struct diffgrep_cb *data = priv;
 	regmatch_t regmatch;

 	if (line[0] != '+' && line[0] != '-')
 		return 0;
 	if (data->hit)
 		BUG("Already matched in diffgrep_consume! Broken xdiff_emit_line_fn?");
 	if (!regexec_buf(data->regexp, line + 1, len - 1, 1,
 			 &regmatch, 0)) {
 		data->hit = 1;
 		return 1;
 	}
 	return 0;
 }

 static int diff_grep(mmfile_t *one, mmfile_t *two,
 		     struct diff_options *o,
 		     regex_t *regexp, kwset_t kws UNUSED)
 {
 	struct diffgrep_cb ecbdata;
 	xpparam_t xpp;
 	xdemitconf_t xecfg;
 	int ret;

 	/*
 	 * We have both sides; need to run textual diff and see if
 	 * the pattern appears on added/deleted lines.
 	 */
 	memset(&xpp, 0, sizeof(xpp));
 	memset(&xecfg, 0, sizeof(xecfg));
 	ecbdata.regexp = regexp;
 	ecbdata.hit = 0;
 	xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
 	xecfg.ctxlen = o->context;
 	xecfg.interhunkctxlen = o->interhunkcontext;

 	/*
 	 * An xdiff error might be our "data->hit" from above. See the
 	 * comment for xdiff_emit_line_fn in xdiff-interface.h
 	 */
 	ret = xdi_diff_outf(one, two, NULL, diffgrep_consume,
 			    &ecbdata, &xpp, &xecfg);
 	if (ecbdata.hit)
 		return 1;
 	if (ret)
 		return ret;
 	return 0;
 }

 static unsigned int contains(mmfile_t *mf, regex_t *regexp, kwset_t kws,
 			     unsigned int limit)
 {
 	unsigned int cnt = 0;
 	unsigned long sz = mf->size;
 	const char *data = mf->ptr;

 	if (regexp) {
 		regmatch_t regmatch;
 		int flags = 0;

 		while (sz &&
 		       !regexec_buf(regexp, data, sz, 1, &regmatch, flags)) {
 			flags |= REG_NOTBOL;
 			data += regmatch.rm_eo;
 			sz -= regmatch.rm_eo;
 			if (sz && regmatch.rm_so == regmatch.rm_eo) {
 				data++;
 				sz--;
 			}
 			cnt++;

 			if (limit && cnt == limit)
 				return cnt;
 		}

 	} else { /* Classic exact string match */
 		while (sz) {
 			struct kwsmatch kwsm;
 			size_t offset = kwsexec(kws, data, sz, &kwsm);
 			if (offset == -1)
 				break;
 			sz -= offset + kwsm.size[0];
 			data += offset + kwsm.size[0];
 			cnt++;

 			if (limit && cnt == limit)
 				return cnt;
 		}
 	}
 	return cnt;
 }

 static int has_changes(mmfile_t *one, mmfile_t *two,
 		       struct diff_options *o UNUSED,
 		       regex_t *regexp, kwset_t kws)
 {
 	unsigned int c1 = one ? contains(one, regexp, kws, 0) : 0;
 	unsigned int c2 = two ? contains(two, regexp, kws, c1 + 1) : 0;
 	return c1 != c2;
 }

 static int pickaxe_match(struct diff_filepair *p, struct diff_options *o,
 			 regex_t *regexp, kwset_t kws, pickaxe_fn fn)
 {
 	struct userdiff_driver *textconv_one = NULL;
 	struct userdiff_driver *textconv_two = NULL;
 	mmfile_t mf1, mf2;
 	int ret;

 	/* ignore unmerged */
 	if (!DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two))
 		return 0;

 	if (o->objfind) {
 		return  (DIFF_FILE_VALID(p->one) &&
 			 oidset_contains(o->objfind, &p->one->oid)) ||
 			(DIFF_FILE_VALID(p->two) &&
 			 oidset_contains(o->objfind, &p->two->oid));
 	}

 	if (o->flags.allow_textconv) {
 		textconv_one = get_textconv(o->repo, p->one);
 		textconv_two = get_textconv(o->repo, p->two);
 	}

 	/*
 	 * If we have an unmodified pair, we know that the count will be the
 	 * same and don't even have to load the blobs. Unless textconv is in
 	 * play, _and_ we are using two different textconv filters (e.g.,
 	 * because a pair is an exact rename with different textconv attributes
 	 * for each side, which might generate different content).
 	 */
 	if (textconv_one == textconv_two && diff_unmodified_pair(p))
 		return 0;

 	if ((o->pickaxe_opts & DIFF_PICKAXE_KIND_G) &&
 	    !o->flags.text &&
 	    ((!textconv_one && diff_filespec_is_binary(o->repo, p->one)) ||
 	     (!textconv_two && diff_filespec_is_binary(o->repo, p->two))))
 		return 0;

 	mf1.size = fill_textconv(o->repo, textconv_one, p->one, &mf1.ptr);
 	mf2.size = fill_textconv(o->repo, textconv_two, p->two, &mf2.ptr);

 	ret = fn(&mf1, &mf2, o, regexp, kws);

 	if (textconv_one)
 		free(mf1.ptr);
 	if (textconv_two)
 		free(mf2.ptr);
 	diff_free_filespec_data(p->one);
 	diff_free_filespec_data(p->two);

 	return ret;
 }

 static void pickaxe(struct diff_queue_struct *q, struct diff_options *o,
 		    regex_t *regexp, kwset_t kws, pickaxe_fn fn)
 {
 	int i;
 	struct diff_queue_struct outq;

 	DIFF_QUEUE_CLEAR(&outq);

 	if (o->pickaxe_opts & DIFF_PICKAXE_ALL) {
 		/* Showing the whole changeset if needle exists */
 		for (i = 0; i < q->nr; i++) {
 			struct diff_filepair *p = q->queue[i];
 			if (pickaxe_match(p, o, regexp, kws, fn))
 				return; /* do not munge the queue */
 		}

 		/*
 		 * Otherwise we will clear the whole queue by copying
 		 * the empty outq at the end of this function, but
 		 * first clear the current entries in the queue.
 		 */
 		for (i = 0; i < q->nr; i++)
 			diff_free_filepair(q->queue[i]);
 	} else {
 		/* Showing only the filepairs that has the needle */
 		for (i = 0; i < q->nr; i++) {
 			struct diff_filepair *p = q->queue[i];
 			if (pickaxe_match(p, o, regexp, kws, fn))
 				diff_q(&outq, p);
 			else
 				diff_free_filepair(p);
 		}
 	}

 	free(q->queue);
 	*q = outq;
 }

 static void regcomp_or_die(regex_t *regex, const char *needle, int cflags)
 {
 	int err = regcomp(regex, needle, cflags);
 	if (err) {
 		/* The POSIX.2 people are surely sick */
 		char errbuf[1024];
 		regerror(err, regex, errbuf, 1024);
 		die("invalid regex: %s", errbuf);
 	}
 }

 void diffcore_pickaxe(struct diff_options *o)
 {
 	const char *needle = o->pickaxe;
 	int opts = o->pickaxe_opts;
 	regex_t regex, *regexp = NULL;
 	kwset_t kws = NULL;
 	pickaxe_fn fn;

 	if (opts & ~DIFF_PICKAXE_KIND_OBJFIND &&
 	    (!needle || !*needle))
 		BUG("should have needle under -G or -S");
 	if (opts & (DIFF_PICKAXE_REGEX | DIFF_PICKAXE_KIND_G)) {
 		int cflags = REG_EXTENDED | REG_NEWLINE;
 		if (o->pickaxe_opts & DIFF_PICKAXE_IGNORE_CASE)
 			cflags |= REG_ICASE;
 		regcomp_or_die(&regex, needle, cflags);
 		regexp = &regex;

 		if (opts & DIFF_PICKAXE_KIND_G)
 			fn = diff_grep;
 		else if (opts & DIFF_PICKAXE_REGEX)
 			fn = has_changes;
 		else
 			/*
 			 * We don't need to check the combination of
 			 * -G and --pickaxe-regex, by the time we get
 			 * here diff.c has already died if they're
 			 * combined. See the usage tests in
 			 * t4209-log-pickaxe.sh.
 			 */
 			BUG("unreachable");
 	} else if (opts & DIFF_PICKAXE_KIND_S) {
 		if (o->pickaxe_opts & DIFF_PICKAXE_IGNORE_CASE &&
 		    has_non_ascii(needle)) {
 			struct strbuf sb = STRBUF_INIT;
 			int cflags = REG_NEWLINE | REG_ICASE;

 			basic_regex_quote_buf(&sb, needle);
 			regcomp_or_die(&regex, sb.buf, cflags);
 			strbuf_release(&sb);
 			regexp = &regex;
 		} else {
 			kws = kwsalloc(o->pickaxe_opts & DIFF_PICKAXE_IGNORE_CASE
 				       ? tolower_trans_tbl : NULL);
 			kwsincr(kws, needle, strlen(needle));
 			kwsprep(kws);
 		}
 		fn = has_changes;
 	} else if (opts & DIFF_PICKAXE_KIND_OBJFIND) {
 		fn = NULL;
 	} else {
 		BUG("unknown pickaxe_opts flag");
 	}

 	pickaxe(&diff_queued_diff, o, regexp, kws, fn);

 	if (regexp)
 		regfree(regexp);
 	if (kws)
 		kwsfree(kws);
 	return;
 }
	/*
	* Copyright (C) 2005 Junio C Hamano
	* Copyright (C) 2010 Google Inc.
	*/
	#include "git-compat-util.h"
	#include "diff.h"
	#include "diffcore.h"
	#include "xdiff-interface.h"
	#include "kwset.h"
	#include "oidset.h"
	#include "pretty.h"
	#include "quote.h"

	typedef int (pickaxe_fn)(mmfile_t one, mmfile_t *two,
	struct diff_options *o,
	regex_t *regexp, kwset_t kws);

	struct diffgrep_cb {
	regex_t *regexp;
	int hit;
	};

	static int diffgrep_consume(void priv, char line, unsigned long len)
	{
	struct diffgrep_cb *data = priv;
	regmatch_t regmatch;

	if (line[0] != '+' && line[0] != '-')
	return 0;
	if (data->hit)
	BUG("Already matched in diffgrep_consume! Broken xdiff_emit_line_fn?");
	if (!regexec_buf(data->regexp, line + 1, len - 1, 1,
	&regmatch, 0)) {
	data->hit = 1;
	return 1;
	}
	return 0;
	}

	static int diff_grep(mmfile_t one, mmfile_t two,
	struct diff_options *o,
	regex_t *regexp, kwset_t kws UNUSED)
	{
	struct diffgrep_cb ecbdata;
	xpparam_t xpp;
	xdemitconf_t xecfg;
	int ret;

	/*
	* We have both sides; need to run textual diff and see if
	* the pattern appears on added/deleted lines.
	*/
	memset(&xpp, 0, sizeof(xpp));
	memset(&xecfg, 0, sizeof(xecfg));
	ecbdata.regexp = regexp;
	ecbdata.hit = 0;
	xecfg.flags = XDL_EMIT_NO_HUNK_HDR;
	xecfg.ctxlen = o->context;
	xecfg.interhunkctxlen = o->interhunkcontext;

	/*
	* An xdiff error might be our "data->hit" from above. See the
	* comment for xdiff_emit_line_fn in xdiff-interface.h
	*/
	ret = xdi_diff_outf(one, two, NULL, diffgrep_consume,
	&ecbdata, &xpp, &xecfg);
	if (ecbdata.hit)
	return 1;
	if (ret)
	return ret;
	return 0;
	}

	static unsigned int contains(mmfile_t mf, regex_t regexp, kwset_t kws,
	unsigned int limit)
	{
	unsigned int cnt = 0;
	unsigned long sz = mf->size;
	const char *data = mf->ptr;

	if (regexp) {
	regmatch_t regmatch;
	int flags = 0;

	while (sz &&
	!regexec_buf(regexp, data, sz, 1, &regmatch, flags)) {
	flags \|= REG_NOTBOL;
	data += regmatch.rm_eo;
	sz -= regmatch.rm_eo;
	if (sz && regmatch.rm_so == regmatch.rm_eo) {
	data++;
	sz--;
	}
	cnt++;

	if (limit && cnt == limit)
	return cnt;
	}

	} else { /* Classic exact string match */
	while (sz) {
	struct kwsmatch kwsm;
	size_t offset = kwsexec(kws, data, sz, &kwsm);
	if (offset == -1)
	break;
	sz -= offset + kwsm.size[0];
	data += offset + kwsm.size[0];
	cnt++;

	if (limit && cnt == limit)
	return cnt;
	}
	}
	return cnt;
	}

	static int has_changes(mmfile_t one, mmfile_t two,
	struct diff_options *o UNUSED,
	regex_t *regexp, kwset_t kws)
	{
	unsigned int c1 = one ? contains(one, regexp, kws, 0) : 0;
	unsigned int c2 = two ? contains(two, regexp, kws, c1 + 1) : 0;
	return c1 != c2;
	}

	static int pickaxe_match(struct diff_filepair p, struct diff_options o,
	regex_t *regexp, kwset_t kws, pickaxe_fn fn)
	{
	struct userdiff_driver *textconv_one = NULL;
	struct userdiff_driver *textconv_two = NULL;
	mmfile_t mf1, mf2;
	int ret;

	/* ignore unmerged */
	if (!DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two))
	return 0;

	if (o->objfind) {
	return (DIFF_FILE_VALID(p->one) &&
	oidset_contains(o->objfind, &p->one->oid)) \|\|
	(DIFF_FILE_VALID(p->two) &&
	oidset_contains(o->objfind, &p->two->oid));
	}

	if (o->flags.allow_textconv) {
	textconv_one = get_textconv(o->repo, p->one);
	textconv_two = get_textconv(o->repo, p->two);
	}

	/*
	* If we have an unmodified pair, we know that the count will be the
	* same and don't even have to load the blobs. Unless textconv is in
	* play, _and_ we are using two different textconv filters (e.g.,
	* because a pair is an exact rename with different textconv attributes
	* for each side, which might generate different content).
	*/
	if (textconv_one == textconv_two && diff_unmodified_pair(p))
	return 0;

	if ((o->pickaxe_opts & DIFF_PICKAXE_KIND_G) &&
	!o->flags.text &&
	((!textconv_one && diff_filespec_is_binary(o->repo, p->one)) \|\|
	(!textconv_two && diff_filespec_is_binary(o->repo, p->two))))
	return 0;

	mf1.size = fill_textconv(o->repo, textconv_one, p->one, &mf1.ptr);
	mf2.size = fill_textconv(o->repo, textconv_two, p->two, &mf2.ptr);

	ret = fn(&mf1, &mf2, o, regexp, kws);

	if (textconv_one)
	free(mf1.ptr);
	if (textconv_two)
	free(mf2.ptr);
	diff_free_filespec_data(p->one);
	diff_free_filespec_data(p->two);

	return ret;
	}

	static void pickaxe(struct diff_queue_struct q, struct diff_options o,
	regex_t *regexp, kwset_t kws, pickaxe_fn fn)
	{
	int i;
	struct diff_queue_struct outq;

	DIFF_QUEUE_CLEAR(&outq);

	if (o->pickaxe_opts & DIFF_PICKAXE_ALL) {
	/* Showing the whole changeset if needle exists */
	for (i = 0; i < q->nr; i++) {
	struct diff_filepair *p = q->queue[i];
	if (pickaxe_match(p, o, regexp, kws, fn))
	return; /* do not munge the queue */
	}

	/*
	* Otherwise we will clear the whole queue by copying
	* the empty outq at the end of this function, but
	* first clear the current entries in the queue.
	*/
	for (i = 0; i < q->nr; i++)
	diff_free_filepair(q->queue[i]);
	} else {
	/* Showing only the filepairs that has the needle */
	for (i = 0; i < q->nr; i++) {
	struct diff_filepair *p = q->queue[i];
	if (pickaxe_match(p, o, regexp, kws, fn))
	diff_q(&outq, p);
	else
	diff_free_filepair(p);
	}
	}

	free(q->queue);
	*q = outq;
	}

	static void regcomp_or_die(regex_t regex, const char needle, int cflags)
	{
	int err = regcomp(regex, needle, cflags);
	if (err) {
	/* The POSIX.2 people are surely sick */
	char errbuf[1024];
	regerror(err, regex, errbuf, 1024);
	die("invalid regex: %s", errbuf);
	}
	}

	void diffcore_pickaxe(struct diff_options *o)
	{
	const char *needle = o->pickaxe;
	int opts = o->pickaxe_opts;
	regex_t regex, *regexp = NULL;
	kwset_t kws = NULL;
	pickaxe_fn fn;

	if (opts & ~DIFF_PICKAXE_KIND_OBJFIND &&
	(!needle \|\| !*needle))
	BUG("should have needle under -G or -S");
	if (opts & (DIFF_PICKAXE_REGEX \| DIFF_PICKAXE_KIND_G)) {
	int cflags = REG_EXTENDED \| REG_NEWLINE;
	if (o->pickaxe_opts & DIFF_PICKAXE_IGNORE_CASE)
	cflags \|= REG_ICASE;
	regcomp_or_die(&regex, needle, cflags);
	regexp = &regex;

	if (opts & DIFF_PICKAXE_KIND_G)
	fn = diff_grep;
	else if (opts & DIFF_PICKAXE_REGEX)
	fn = has_changes;
	else
	/*
	* We don't need to check the combination of
	* -G and --pickaxe-regex, by the time we get
	* here diff.c has already died if they're
	* combined. See the usage tests in
	* t4209-log-pickaxe.sh.
	*/
	BUG("unreachable");
	} else if (opts & DIFF_PICKAXE_KIND_S) {
	if (o->pickaxe_opts & DIFF_PICKAXE_IGNORE_CASE &&
	has_non_ascii(needle)) {
	struct strbuf sb = STRBUF_INIT;
	int cflags = REG_NEWLINE \| REG_ICASE;

	basic_regex_quote_buf(&sb, needle);
	regcomp_or_die(&regex, sb.buf, cflags);
	strbuf_release(&sb);
	regexp = &regex;
	} else {
	kws = kwsalloc(o->pickaxe_opts & DIFF_PICKAXE_IGNORE_CASE
	? tolower_trans_tbl : NULL);
	kwsincr(kws, needle, strlen(needle));
	kwsprep(kws);
	}
	fn = has_changes;
	} else if (opts & DIFF_PICKAXE_KIND_OBJFIND) {
	fn = NULL;
	} else {
	BUG("unknown pickaxe_opts flag");
	}

	pickaxe(&diff_queued_diff, o, regexp, kws, fn);

	if (regexp)
	regfree(regexp);
	if (kws)
	kwsfree(kws);
	return;
	}