/* * Helper function for splitting a string into an argv-like array. */ #include <linux/kernel.h> #include <linux/ctype.h> #include <linux/string.h> #include <linux/slab.h> #include <linux/export.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++) kfree(*p); kfree(argv); } EXPORT_SYMBOL(argv_free); /** * argv_split - split a string at whitespace, returning an argv * @gfp: the GFP mask used to allocate memory * @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(gfp_t gfp, const char *str, int *argcp) { int argc = count_argc(str); char **argv = kzalloc(sizeof(*argv) * (argc+1), gfp); 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 = kstrndup(p, str-p, gfp); if (t == NULL) goto fail; *argvp++ = t; } } *argvp = NULL; out: return argv; fail: argv_free(argv); return NULL; } EXPORT_SYMBOL(argv_split);