linux-stable/tools/lib/argv_split.c
Arnaldo Carvalho de Melo 9c10548c42 tools lib: Move argv_{split,free} from tools/perf/util/
This came from the kernel lib/argv_split.c, so move it to
tools/lib/argv_split.c, to get it closer to the kernel structure.

We need to audit the usage of argv_split() to figure out if it is really
necessary to do have one allocation per argv[] entry, looking at one of
its users I guess that is not the case and we probably are even leaking
those allocations by not using argv_free() judiciously, for later.

With this we further remove stuff from tools/perf/util/, reducing the
perf specific codebase and encouraging other tools/ code to use these
routines so as to keep the style and constructs used with the kernel.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-j479s1ive9h75w5lfg16jroz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-01 22:50:40 -03:00

100 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Helper function for splitting a string into an argv-like array.
*/
#include <stdlib.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/string.h>
static const char *skip_arg(const char *cp)
{
while (*cp && !isspace(*cp))
cp++;
return cp;
}
static int count_argc(const char *str)
{
int count = 0;
while (*str) {
str = skip_spaces(str);
if (*str) {
count++;
str = skip_arg(str);
}
}
return count;
}
/**
* argv_free - free an argv
* @argv - the argument vector to be freed
*
* Frees an argv and the strings it points to.
*/
void argv_free(char **argv)
{
char **p;
for (p = argv; *p; p++) {
free(*p);
*p = NULL;
}
free(argv);
}
/**
* argv_split - split a string at whitespace, returning an argv
* @str: the string to be split
* @argcp: returned argument count
*
* Returns an array of pointers to strings which are split out from
* @str. This is performed by strictly splitting on white-space; no
* quote processing is performed. Multiple whitespace characters are
* considered to be a single argument separator. The returned array
* is always NULL-terminated. Returns NULL on memory allocation
* failure.
*/
char **argv_split(const char *str, int *argcp)
{
int argc = count_argc(str);
char **argv = calloc(argc + 1, sizeof(*argv));
char **argvp;
if (argv == NULL)
goto out;
if (argcp)
*argcp = argc;
argvp = argv;
while (*str) {
str = skip_spaces(str);
if (*str) {
const char *p = str;
char *t;
str = skip_arg(str);
t = strndup(p, str-p);
if (t == NULL)
goto fail;
*argvp++ = t;
}
}
*argvp = NULL;
out:
return argv;
fail:
argv_free(argv);
return NULL;
}