1 files changed, 111 insertions, 0 deletions
diff --git a/sapi/phpdbg/phpdbg_sigsafe.c b/sapi/phpdbg/phpdbg_sigsafe.c
new file mode 100644
index 0000000000..7238ad102f
--- /dev/null
+++ b/sapi/phpdbg/phpdbg_sigsafe.c
@@ -0,0 +1,111 @@
+#include "phpdbg_sigsafe.h"
+#include "phpdbg.h"
+
+ZEND_EXTERN_MODULE_GLOBALS(phpdbg);
+
+static inline void zend_mm_init(zend_mm_heap *heap) {
+	zend_mm_free_block *p;
+	int i;
+
+	heap->free_bitmap = 0;
+	heap->large_free_bitmap = 0;
+#if ZEND_MM_CACHE
+	heap->cached = 0;
+	memset(heap->cache, 0, sizeof(heap->cache));
+#endif
+#if ZEND_MM_CACHE_STAT
+	for (i = 0; i < ZEND_MM_NUM_BUCKETS; i++) {
+		heap->cache_stat[i].count = 0;
+	}
+#endif
+	p = ZEND_MM_SMALL_FREE_BUCKET(heap, 0);
+	for (i = 0; i < ZEND_MM_NUM_BUCKETS; i++) {
+		p->next_free_block = p;
+		p->prev_free_block = p;
+		p = (zend_mm_free_block *)((char *)p + sizeof(zend_mm_free_block *) * 2);
+		heap->large_free_buckets[i] = NULL;
+	}
+	heap->rest_buckets[0] = heap->rest_buckets[1] = ZEND_MM_REST_BUCKET(heap);
+	heap->rest_count = 0;
+}
+
+static zend_mm_storage* zend_mm_mem_init(void *params) {
+	TSRMLS_FETCH();
+
+	return &PHPDBG_G(sigsafe_mem).storage;
+}
+
+static void zend_mm_mem_dummy(zend_mm_storage *storage) {
+}
+
+#define STR(x) #x
+#define EXP_STR(x) STR(x)
+
+static zend_mm_segment* zend_mm_mem_alloc(zend_mm_storage *storage, size_t size) {
+	TSRMLS_FETCH();
+
+	if (EXPECTED(size == PHPDBG_SIGSAFE_MEM_SIZE && !PHPDBG_G(sigsafe_mem).allocated)) {
+		PHPDBG_G(sigsafe_mem).allocated = 1;
+		return (zend_mm_segment *) PHPDBG_G(sigsafe_mem).mem;
+	}
+
+	write(PHPDBG_G(io)[PHPDBG_STDERR].fd, ZEND_STRL("Tried to allocate more than " EXP_STR(PHPDBG_SIGSAFE_MEM_SIZE) " bytes from stack memory in signal handler ... bailing out of signal handler\n"));
+
+	if (*EG(bailout)) {
+		LONGJMP(*EG(bailout), FAILURE);
+	}
+
+	write(PHPDBG_G(io)[PHPDBG_STDERR].fd, ZEND_STRL("Bailed out without a bailout address in signal handler!\n"));
+
+	return NULL;
+}
+
+static zend_mm_segment* zend_mm_mem_realloc(zend_mm_storage *storage, zend_mm_segment *ptr, size_t size) {
+	return zend_mm_mem_alloc(storage, size);
+}
+
+static void zend_mm_mem_free(zend_mm_storage *storage, zend_mm_segment *ptr) {
+}
+
+static const zend_mm_mem_handlers phpdbg_handlers_sigsafe_mem = { "stack", zend_mm_mem_init, zend_mm_mem_dummy, zend_mm_mem_dummy, zend_mm_mem_alloc, zend_mm_mem_realloc, zend_mm_mem_free };
+
+void phpdbg_set_sigsafe_mem(char *buffer TSRMLS_DC) {
+	phpdbg_signal_safe_mem *mem = &PHPDBG_G(sigsafe_mem);
+	mem->old_heap = zend_mm_set_heap(&mem->heap TSRMLS_CC);
+	mem->mem = buffer;
+	mem->allocated = 0;
+
+	mem->storage.handlers = &phpdbg_handlers_sigsafe_mem;
+	mem->heap.storage = &mem->storage;
+	mem->heap.block_size = PHPDBG_SIGSAFE_MEM_SIZE;
+	mem->heap.compact_size = 0;
+	mem->heap.segments_list = NULL;
+	zend_mm_init(&mem->heap);
+#if ZEND_MM_CACHE_STAT
+	memset(mem->heap.cache_stat, 0, sizeof(mem->heap.cache_stat));
+#endif
+	mem->heap.use_zend_alloc = 1;
+	mem->heap.real_size = 0;
+	mem->heap.overflow = 0;
+	mem->heap.real_peak = 0;
+	mem->heap.limit = PHPDBG_SIGSAFE_MEM_SIZE;
+	mem->heap.size = 0;
+	mem->heap.peak = 0;
+	mem->heap.internal = 0;
+	mem->heap.reserve = NULL;
+	mem->heap.reserve_size = 0;
+}
+
+zend_mm_heap *phpdbg_original_heap_sigsafe_mem(TSRMLS_D) {
+	return PHPDBG_G(sigsafe_mem).old_heap;
+}
+
+void phpdbg_clear_sigsafe_mem(TSRMLS_D) {
+	zend_mm_set_heap(phpdbg_original_heap_sigsafe_mem(TSRMLS_C) TSRMLS_CC);
+	PHPDBG_G(sigsafe_mem).mem = NULL;
+}
+
+zend_bool phpdbg_active_sigsafe_mem(TSRMLS_D) {
+	return !!PHPDBG_G(sigsafe_mem).mem;
+}
+