101 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * Helper function for splitting a string into an argv-like array.4 */5 6#include <stdlib.h>7#include <linux/kernel.h>8#include <linux/ctype.h>9#include <linux/string.h>10 11static const char *skip_arg(const char *cp)12{13 while (*cp && !isspace(*cp))14 cp++;15 16 return cp;17}18 19static int count_argc(const char *str)20{21 int count = 0;22 23 while (*str) {24 str = skip_spaces(str);25 if (*str) {26 count++;27 str = skip_arg(str);28 }29 }30 31 return count;32}33 34/**35 * argv_free - free an argv36 * @argv - the argument vector to be freed37 *38 * Frees an argv and the strings it points to.39 */40void argv_free(char **argv)41{42 char **p;43 for (p = argv; *p; p++) {44 free(*p);45 *p = NULL;46 }47 48 free(argv);49}50 51/**52 * argv_split - split a string at whitespace, returning an argv53 * @str: the string to be split54 * @argcp: returned argument count55 *56 * Returns an array of pointers to strings which are split out from57 * @str. This is performed by strictly splitting on white-space; no58 * quote processing is performed. Multiple whitespace characters are59 * considered to be a single argument separator. The returned array60 * is always NULL-terminated. Returns NULL on memory allocation61 * failure.62 */63char **argv_split(const char *str, int *argcp)64{65 int argc = count_argc(str);66 char **argv = calloc(argc + 1, sizeof(*argv));67 char **argvp;68 69 if (argv == NULL)70 goto out;71 72 if (argcp)73 *argcp = argc;74 75 argvp = argv;76 77 while (*str) {78 str = skip_spaces(str);79 80 if (*str) {81 const char *p = str;82 char *t;83 84 str = skip_arg(str);85 86 t = strndup(p, str-p);87 if (t == NULL)88 goto fail;89 *argvp++ = t;90 }91 }92 *argvp = NULL;93 94out:95 return argv;96 97fail:98 argv_free(argv);99 return NULL;100}101