Fix va_list usage (for real this time)HEAD1.8master

Signed-off-by: Mattias Andrée <m@maandree.se>

1 files changed, 27 insertions, 25 deletions

diff --git a/vmemalloc.c b/vmemalloc.c
index 2cac8dd..72e65d2 100644
--- a/vmemalloc.c
+++ b/vmemalloc.c
@@ -18,14 +18,16 @@ struct memalloc_state {
 };
 
 static int
-vmemalloc_parse_size_prod(struct memalloc_state *state, size_t n, size_t arg, va_list *ap)
+vmemalloc_parse_size_prod(struct memalloc_state *state, size_t n, size_t arg, va_list ap, size_t *ap_advance_out)
 {
+	*ap_advance_out = 0;
 	if (state->have_size++)
 		goto inval;
 	state->elem_size = arg;
 	if (n) {
 		while (--n) {
-			arg = va_arg(*ap, size_t);
+			arg = va_arg(ap, size_t);
+			++*ap_advance_out;
 			if (!state->elem_size)
 				continue;
 			if (LIBSIMPLE_UMUL_OVERFLOW_NONZERO(arg, state->elem_size, &state->elem_size, SIZE_MAX)) {
@@ -37,7 +39,8 @@ vmemalloc_parse_size_prod(struct memalloc_state *state, size_t n, size_t arg, va
 		if (!arg)
 			goto inval;
 		for (;;) {
-			arg = va_arg(*ap, size_t);
+			arg = va_arg(ap, size_t);
+			++*ap_advance_out;
 			if (!arg)
 				break;
 			if (LIBSIMPLE_UMUL_OVERFLOW_NONZERO(arg, state->elem_size, &state->elem_size, SIZE_MAX)) {
@@ -53,15 +56,15 @@ inval:
 }
 
 static int
-vmemalloc_parse_args(struct memalloc_state *state, size_t n, va_list *ap)
+vmemalloc_parse_args(struct memalloc_state *state, size_t n, va_list ap)
 {
 	enum libsimple_memalloc_option opt;
 	long int page_size;
-	va_list *subap;
-	size_t arg;
+	va_list *subap, ap_copy;
+	size_t arg, ap_advance;
 
 	for (;;) {
-		opt = va_arg(*ap, enum libsimple_memalloc_option);
+		opt = va_arg(ap, enum libsimple_memalloc_option);
 		switch (opt) {
 		case LIBSIMPLE_MEMALLOC_END:
 			return 0;
@@ -75,7 +78,7 @@ vmemalloc_parse_args(struct memalloc_state *state, size_t n, va_list *ap)
 		case LIBSIMPLE_MEMALLOC_CONDITIONAL_ZERO_INIT:
 			if (state->zero_init >= 0)
 				goto inval;
-			state->zero_init = (char)va_arg(*ap, int);
+			state->zero_init = (char)va_arg(ap, int);
 			state->zero_init = !!state->zero_init;
 			break;
 
@@ -89,7 +92,7 @@ vmemalloc_parse_args(struct memalloc_state *state, size_t n, va_list *ap)
 		case LIBSIMPLE_MEMALLOC_ALIGNMENT:
 			if (state->alignment)
 				goto inval;
-			state->alignment = va_arg(*ap, size_t);
+			state->alignment = va_arg(ap, size_t);
 			if (!state->alignment)
 				goto inval;
 			break;
@@ -121,34 +124,38 @@ vmemalloc_parse_args(struct memalloc_state *state, size_t n, va_list *ap)
 		case LIBSIMPLE_MEMALLOC_ELEMENT_SIZE:
 			if (state->elem_size)
 				goto inval;
-			state->elem_size = va_arg(*ap, size_t);
+			state->elem_size = va_arg(ap, size_t);
 			if (!state->elem_size)
 				goto inval;
 			break;
 
 		case LIBSIMPLE_MEMALLOC_PRODUCT_SIZE:
-			arg = va_arg(*ap, size_t);
-			if (vmemalloc_parse_size_prod(state, n, arg, ap))
+			arg = va_arg(ap, size_t);
+			va_copy(ap_copy, ap);
+			if (vmemalloc_parse_size_prod(state, n, arg, ap_copy, &ap_advance))
 				return -1;
+			va_end(ap_copy);
+			while (ap_advance--)
+				(void) va_arg(ap, size_t);
 			break;
 
 		case LIBSIMPLE_MEMALLOC_VA_PRODUCT_SIZE:
-			subap = va_arg(*ap, va_list *);
+			subap = va_arg(ap, va_list *);
 			arg = va_arg(*subap, size_t);
-			if (vmemalloc_parse_size_prod(state, n, arg, subap))
+			if (vmemalloc_parse_size_prod(state, n, arg, *subap, &ap_advance))
 				return -1;
 			break;
 
 		case LIBSIMPLE_MEMALLOC_1_VA_PRODUCT_SIZE:
-			arg = va_arg(*ap, size_t);
-			subap = va_arg(*ap, va_list *);
-			if (vmemalloc_parse_size_prod(state, n, arg, subap))
+			arg = va_arg(ap, size_t);
+			subap = va_arg(ap, va_list *);
+			if (vmemalloc_parse_size_prod(state, n, arg, *subap, &ap_advance))
 				return -1;
 			break;
 
 		case LIBSIMPLE_MEMALLOC_VA_LIST:
-			subap = va_arg(*ap, va_list *);
-			if (vmemalloc_parse_args(state, n, subap))
+			subap = va_arg(ap, va_list *);
+			if (vmemalloc_parse_args(state, n, *subap))
 				return -1;
 			break;
 
@@ -198,9 +205,6 @@ libsimple_vmemalloc(size_t n, va_list ap) /* TODO test ([v]{mem,array}alloc) */
 	void *ptr = NULL;
 	int saved_errno;
 	long int tmp;
-	va_list ap_copy; /* required because `ap` may be an array (specific single-element array)
-	                  * that has decayed into a pointer, and so &ap would not be a `va_list *`
-	                  * and casting to `void *` could just obfuscate this critical error */
 
 	state.alignment     = 0;
 	state.elem_size     = 0;
@@ -212,10 +216,8 @@ libsimple_vmemalloc(size_t n, va_list ap) /* TODO test ([v]{mem,array}alloc) */
 	state.cache_align   = 0;
 	state.cache_split   = 0;
 
-	va_copy(ap_copy, ap);
-	if (vmemalloc_parse_args(&state, n, &ap_copy))
+	if (vmemalloc_parse_args(&state, n, ap))
 		return NULL;
-	va_end(ap_copy);
 
 	state.elem_size = state.elem_size ? state.elem_size : 1;
 	state.zero_init = state.zero_init >= 0 ? state.zero_init : 0;