Commit 313026f3 authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google) Committed by Arnaldo Carvalho de Melo
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perf string: Add strpbrk_esq() and strdup_esq() for escape and quote 



strpbrk_esq() and strdup_esq() are new variants for strpbrk() and
strdup() which handles escaped characters and quoted strings.

- strpbrk_esq() searches specified set of characters but ignores the
  escaped characters and quoted strings.
  e.g. strpbrk_esq("'quote\d' \queue quiz", "qd") returns "quiz".

- strdup_esq() duplicates string but removes backslash and quotes which
  is used for quotation. It also keeps the string (including backslash)
  in the quoted part.
  e.g. strdup_esq("'quote\d' \queue quiz") returns "quote\d queue quiz".

The (single, double) quotes in the quoted part should be escaped by
backslash. In this case, strdup_esq() removes that backslash.
The same quotes must be paired. If you use double quotation, you need
to use the double quotation to close the quoted part.

Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/173099116045.2431889.15772916605719019533.stgit@mhiramat.roam.corp.google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent b9e57722

tools/perf/util/string.c

+100 −0
Original line number Diff line number Diff line
@@ -263,6 +263,34 @@ char *strpbrk_esc(char *str, const char *stopset) 
	return ptr;

}



/* Like strpbrk_esc(), but not break if it is quoted with single/double quotes */

char *strpbrk_esq(char *str, const char *stopset)

{

	char *_stopset = NULL;

	char *ptr;

	const char *squote = "'";

	const char *dquote = "\"";



	if (asprintf(&_stopset, "%s%c%c", stopset, *squote, *dquote) < 0)

		return NULL;



	do {

		ptr = strpbrk_esc(str, _stopset);

		if (!ptr)

			break;

		if (*ptr == *squote)

			ptr = strpbrk_esc(ptr + 1, squote);

		else if (*ptr == *dquote)

			ptr = strpbrk_esc(ptr + 1, dquote);

		else

			break;

		str = ptr + 1;

	} while (ptr);



	free(_stopset);

	return ptr;

}



/* Like strdup, but do not copy a single backslash */

char *strdup_esc(const char *str)

{
@@ -293,6 +321,78 @@ char *strdup_esc(const char *str) 
	return ret;

}



/* Remove backslash right before quote and return next quote address. */

static char *remove_consumed_esc(char *str, int len, int quote)

{

	char *ptr = str, *end = str + len;



	while (*ptr != quote && ptr < end) {

		if (*ptr == '\\' && *(ptr + 1) == quote) {

			memmove(ptr, ptr + 1, end - (ptr + 1));

			/* now *ptr is `quote`. */

			end--;

		}

		ptr++;

	}



	return *ptr == quote ? ptr : NULL;

}



/*

 * Like strdup_esc, but keep quoted string as it is (and single backslash

 * before quote is removed). If there is no closed quote, return NULL.

 */

char *strdup_esq(const char *str)

{

	char *d, *ret;



	/* If there is no quote, return normal strdup_esc() */

	d = strpbrk_esc((char *)str, "\"'");

	if (!d)

		return strdup_esc(str);



	ret = strdup(str);

	if (!ret)

		return NULL;



	d = ret;

	do {

		d = strpbrk(d, "\\\"\'");

		if (!d)

			break;



		if (*d == '"' || *d == '\'') {

			/* This is non-escaped quote */

			int quote = *d;

			int len = strlen(d + 1) + 1;



			/*

			 * Remove the start quote and remove consumed escape (backslash

			 * before quote) and remove the end quote. If there is no end

			 * quote, it is the input error.

			 */

			memmove(d, d + 1, len);

			d = remove_consumed_esc(d, len, quote);

			if (!d)

				goto error;

			memmove(d, d + 1, strlen(d + 1) + 1);

		}

		if (*d == '\\') {

			memmove(d, d + 1, strlen(d + 1) + 1);

			if (*d == '\\') {

				/* double backslash -- keep the second one. */

				d++;

			}

		}

	} while (*d != '\0');



	return ret;



error:

	free(ret);

	return NULL;

}



unsigned int hex(char c)

{

	if (c >= '0' && c <= '9')

tools/perf/util/string2.h

+2 −0
Original line number Diff line number Diff line
@@ -37,6 +37,8 @@ char *asprintf__tp_filter_pids(size_t npids, pid_t *pids); 


char *strpbrk_esc(char *str, const char *stopset);

char *strdup_esc(const char *str);

char *strpbrk_esq(char *str, const char *stopset);

char *strdup_esq(const char *str);



unsigned int hex(char c);

char *strreplace_chars(char needle, const char *haystack, const char *replace);