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/* See LICENSE file for copyright and license details. */
#include "common.h"
#ifndef TEST
#if defined(WITH_BACKTRACE) && defined(__GNUC__)
# pragma GCC diagnostic ignored "-Walloca"
#endif
static _Thread_local int inside_mmap_anon = 0;
static void
meminfo_fixup(struct meminfo *meminfo)
{
if (meminfo->alignment_type == DEFAULT_ALIGNMENT)
meminfo->requested_alignment = _Alignof(max_align_t);
else if (meminfo->alignment_type == PAGE_ALIGNMENT)
meminfo->requested_alignment = libtest_get_pagesize();
meminfo->actual_alignment = meminfo->requested_alignment;
meminfo->accept_leakage = !!libtest_malloc_accept_leakage;
if (libtest_zero_on_alloc)
meminfo->initialised_on_alloc |= !meminfo->accept_leakage;
}
static int
add_or_enomem(size_t *augend, size_t augment)
{
if (*augend > SIZE_MAX - augment) {
errno = ENOMEM;
return -1;
}
*augend += augment;
return 0;
}
static void *
mmap_anon(size_t size)
{
void *ptr;
inside_mmap_anon = 1;
ptr = libtest_real_mmap(NULL, size,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_UNINITIALIZED,
-1, 0);
inside_mmap_anon = 0;
return ptr == MAP_FAILED ? NULL : ptr;
}
void *
libtest_alloc(struct meminfo *meminfo)
{
static _Thread_local int recursion_guard = 0;
void *base_ptr, *ret_ptr;
size_t misalignment;
size_t bookkeeping;
int saved_errno;
#ifdef WITH_BACKTRACE
size_t backtrace_realignment;
size_t i, backtrace_n;
unw_cursor_t cursor;
unw_context_t context;
unw_word_t rip;
struct partial {
uintptr_t rips[8];
struct partial *next;
} *current, head;
#endif
assert(!inside_mmap_anon);
saved_errno = errno;
meminfo_fixup(meminfo);
#ifdef WITH_BACKTRACE
meminfo->accept_leakage |= libtest_malloc_internal_usage > 0;
#endif
/* Get backtrace (have to do it now to calculate `backtrace_n` for allocation) */
#ifdef WITH_BACKTRACE
backtrace_n = 0u;
if (!libtest_malloc_accept_leakage && !libtest_malloc_internal_usage) {
libtest_malloc_internal_usage++;
if (unw_getcontext(&context) || unw_init_local(&cursor, &context))
goto skip_backtrace;
for (current = &head, i = 0u; unw_step(&cursor) > 0; i++) {
if (i % ELEMSOF(current->rips) == 0u)
current = current->next = alloca(sizeof(*current));
if (unw_get_reg(&cursor, UNW_REG_IP, &rip))
goto skip_backtrace;
current->rips[i % ELEMSOF(current->rips)] = (uintptr_t)rip;
}
backtrace_n = i;
skip_backtrace:
libtest_malloc_internal_usage--;
}
#endif
/* Calculate required alloction size */
meminfo->real_alloc_size = meminfo->requested_alloc_size;
if (add_or_enomem(&meminfo->real_alloc_size, sizeof(struct meminfo)) ||
add_or_enomem(&meminfo->real_alloc_size, _Alignof(void *) + sizeof(void *)) ||
add_or_enomem(&meminfo->real_alloc_size, meminfo->actual_alignment))
return NULL;
#ifdef WITH_BACKTRACE
if (backtrace_n) {
misalignment = sizeof(struct meminfo) % _Alignof(struct backtrace);
backtrace_realignment = misalignment ? _Alignof(struct backtrace) - misalignment : 0u;
if (add_or_enomem(&meminfo->real_alloc_size, backtrace_realignment) ||
add_or_enomem(&meminfo->real_alloc_size, offsetof(struct backtrace, trace)) ||
add_or_enomem(&meminfo->real_alloc_size, backtrace_n * sizeof(Dwarf_Addr)))
return NULL;
}
#endif
bookkeeping = meminfo->real_alloc_size - meminfo->requested_alloc_size;
bookkeeping -= meminfo->actual_alignment;
/* Allocate memory */
base_ptr = mmap_anon(meminfo->real_alloc_size);
if (!base_ptr)
return NULL;
if (meminfo->initialised_on_alloc)
memset(base_ptr, 0, meminfo->real_alloc_size);
ret_ptr = &((char *)base_ptr)[bookkeeping];
/* Save backtrace */
#ifdef WITH_BACKTRACE
if (backtrace_n) {
meminfo->backtrace = (void *)&((char *)base_ptr)[sizeof(struct meminfo) + backtrace_realignment];
meminfo->backtrace->n = backtrace_n;
for (current = &head, i = 0u; i < backtrace_n; i++) {
if (i % ELEMSOF(current->rips) == 0u)
current = current->next;
meminfo->backtrace->trace[i] = current->rips[i % ELEMSOF(current->rips)];
}
} else {
meminfo->backtrace = NULL;
}
#endif
/* Fix alignment */
misalignment = (size_t)(uintptr_t)ret_ptr % meminfo->actual_alignment;
if (misalignment)
ret_ptr = &((char *)ret_ptr)[meminfo->actual_alignment - misalignment];
/* Store usable size */
meminfo->usable_alloc_size = meminfo->real_alloc_size;
meminfo->usable_alloc_size -= (size_t)((char *)ret_ptr - (char *)base_ptr);
/* Store book-keeping */
meminfo->usable_area = ret_ptr;
memcpy(base_ptr, meminfo, sizeof(*meminfo));
BASE_POINTER(ret_ptr) = base_ptr;
meminfo = base_ptr;
/* Track allocation */
if (!libtest_kill_malloc_tracking) {
assert(!recursion_guard);
recursion_guard = 1;
SPINLOCK(libtest_allocs_list_spinlock);
if (!libtest_allocs_list_inited) {
libtest_allocs_head.prev = NULL;
libtest_allocs_head.next = &libtest_allocs_tail;
libtest_allocs_tail.prev = &libtest_allocs_head;
libtest_allocs_tail.next = NULL;
libtest_allocs_list_inited = 1;
}
libtest_allocs_tail.prev->next = meminfo;
meminfo->prev = libtest_allocs_tail.prev;
meminfo->next = &libtest_allocs_tail;
SPINUNLOCK(libtest_allocs_list_spinlock);
recursion_guard = 0;
}
/* Optionally print out trace */
#ifdef WITH_BACKTRACE
if (meminfo->backtrace && !libtest_malloc_internal_usage && getenv("TRACE_MALLOC")) {
libtest_malloc_internal_usage++;
fprintf(stderr, "Memory allocated: %p (alloc-size=%zu, real-size=%zu, leak-allowed=%i)\n",
ret_ptr, meminfo->requested_alloc_size, meminfo->real_alloc_size, meminfo->accept_leakage);
libtest_print_backtrace(stderr, "\tat ", 0u, NULL);
fflush(stderr);
libtest_malloc_internal_usage--;
}
#endif
errno = saved_errno;
return ret_ptr;
}
#else
CONST int
main(void)
{
/* Tested via alloc.c */
return 0;
}
#endif
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