/* * linux/lib/kasprintf.c * * Copyright (C) 1991, 1992 Linus Torvalds */ #include <stdarg.h> #include <linux/export.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/string.h> /* Simplified asprintf. */ char *kvasprintf(gfp_t gfp, const char *fmt, va_list ap) { unsigned int len; char *p; va_list aq; va_copy(aq, ap); len = vsnprintf(NULL, 0, fmt, aq); va_end(aq); p = kmalloc_track_caller(len+1, gfp); if (!p) return NULL; vsnprintf(p, len+1, fmt, ap); return p; } EXPORT_SYMBOL(kvasprintf); /* * If fmt contains no % (or is exactly %s), use kstrdup_const. If fmt * (or the sole vararg) points to rodata, we will then save a memory * allocation and string copy. In any case, the return value should be * freed using kfree_const(). */ const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list ap) { if (!strchr(fmt, '%')) return kstrdup_const(fmt, gfp); if (!strcmp(fmt, "%s")) return kstrdup_const(va_arg(ap, const char*), gfp); return kvasprintf(gfp, fmt, ap); } EXPORT_SYMBOL(kvasprintf_const); char *kasprintf(gfp_t gfp, const char *fmt, ...) { va_list ap; char *p; va_start(ap, fmt); p = kvasprintf(gfp, fmt, ap); va_end(ap); return p; } EXPORT_SYMBOL(kasprintf);