From 80372d4ca082d6d35f89e99094544fc892cfeb75 Mon Sep 17 00:00:00 2001 From: Andrei Karas Date: Tue, 26 Nov 2019 03:09:38 +0300 Subject: Add libbacktrace --- 3rdparty/libbacktrace/mmap.c | 325 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 325 insertions(+) create mode 100644 3rdparty/libbacktrace/mmap.c (limited to '3rdparty/libbacktrace/mmap.c') diff --git a/3rdparty/libbacktrace/mmap.c b/3rdparty/libbacktrace/mmap.c new file mode 100644 index 000000000..32fcba623 --- /dev/null +++ b/3rdparty/libbacktrace/mmap.c @@ -0,0 +1,325 @@ +/* mmap.c -- Memory allocation with mmap. + Copyright (C) 2012-2018 Free Software Foundation, Inc. + Written by Ian Lance Taylor, Google. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + (1) Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + + (2) Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in + the documentation and/or other materials provided with the + distribution. + + (3) The name of the author may not be used to + endorse or promote products derived from this software without + specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, +INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, +STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING +IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +POSSIBILITY OF SUCH DAMAGE. */ + +#include "config.h" + +#include +#include +#include +#include +#include +#include + +#include "backtrace.h" +#include "internal.h" + +/* Memory allocation on systems that provide anonymous mmap. This + permits the backtrace functions to be invoked from a signal + handler, assuming that mmap is async-signal safe. */ + +#ifndef MAP_ANONYMOUS +#define MAP_ANONYMOUS MAP_ANON +#endif + +#ifndef MAP_FAILED +#define MAP_FAILED ((void *)-1) +#endif + +/* A list of free memory blocks. */ + +struct backtrace_freelist_struct +{ + /* Next on list. */ + struct backtrace_freelist_struct *next; + /* Size of this block, including this structure. */ + size_t size; +}; + +/* Free memory allocated by backtrace_alloc. */ + +static void +backtrace_free_locked (struct backtrace_state *state, void *addr, size_t size) +{ + /* Just leak small blocks. We don't have to be perfect. Don't put + more than 16 entries on the free list, to avoid wasting time + searching when allocating a block. If we have more than 16 + entries, leak the smallest entry. */ + + if (size >= sizeof (struct backtrace_freelist_struct)) + { + size_t c; + struct backtrace_freelist_struct **ppsmall; + struct backtrace_freelist_struct **pp; + struct backtrace_freelist_struct *p; + + c = 0; + ppsmall = NULL; + for (pp = &state->freelist; *pp != NULL; pp = &(*pp)->next) + { + if (ppsmall == NULL || (*pp)->size < (*ppsmall)->size) + ppsmall = pp; + ++c; + } + if (c >= 16) + { + if (size <= (*ppsmall)->size) + return; + *ppsmall = (*ppsmall)->next; + } + + p = (struct backtrace_freelist_struct *) addr; + p->next = state->freelist; + p->size = size; + state->freelist = p; + } +} + +/* Allocate memory like malloc. If ERROR_CALLBACK is NULL, don't + report an error. */ + +void * +backtrace_alloc (struct backtrace_state *state, + size_t size, backtrace_error_callback error_callback, + void *data) +{ + void *ret; + int locked; + struct backtrace_freelist_struct **pp; + size_t pagesize; + size_t asksize; + void *page; + + ret = NULL; + + /* If we can acquire the lock, then see if there is space on the + free list. If we can't acquire the lock, drop straight into + using mmap. __sync_lock_test_and_set returns the old state of + the lock, so we have acquired it if it returns 0. */ + + if (!state->threaded) + locked = 1; + else + locked = __sync_lock_test_and_set (&state->lock_alloc, 1) == 0; + + if (locked) + { + for (pp = &state->freelist; *pp != NULL; pp = &(*pp)->next) + { + if ((*pp)->size >= size) + { + struct backtrace_freelist_struct *p; + + p = *pp; + *pp = p->next; + + /* Round for alignment; we assume that no type we care about + is more than 8 bytes. */ + size = (size + 7) & ~ (size_t) 7; + if (size < p->size) + backtrace_free_locked (state, (char *) p + size, + p->size - size); + + ret = (void *) p; + + break; + } + } + + if (state->threaded) + __sync_lock_release (&state->lock_alloc); + } + + if (ret == NULL) + { + /* Allocate a new page. */ + + pagesize = getpagesize (); + asksize = (size + pagesize - 1) & ~ (pagesize - 1); + page = mmap (NULL, asksize, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (page == MAP_FAILED) + { + if (error_callback) + error_callback (data, "mmap", errno); + } + else + { + size = (size + 7) & ~ (size_t) 7; + if (size < asksize) + backtrace_free (state, (char *) page + size, asksize - size, + error_callback, data); + + ret = page; + } + } + + return ret; +} + +/* Free memory allocated by backtrace_alloc. */ + +void +backtrace_free (struct backtrace_state *state, void *addr, size_t size, + backtrace_error_callback error_callback ATTRIBUTE_UNUSED, + void *data ATTRIBUTE_UNUSED) +{ + int locked; + + /* If we are freeing a large aligned block, just release it back to + the system. This case arises when growing a vector for a large + binary with lots of debug info. Calling munmap here may cause us + to call mmap again if there is also a large shared library; we + just live with that. */ + if (size >= 16 * 4096) + { + size_t pagesize; + + pagesize = getpagesize (); + if (((uintptr_t) addr & (pagesize - 1)) == 0 + && (size & (pagesize - 1)) == 0) + { + /* If munmap fails for some reason, just add the block to + the freelist. */ + if (munmap (addr, size) == 0) + return; + } + } + + /* If we can acquire the lock, add the new space to the free list. + If we can't acquire the lock, just leak the memory. + __sync_lock_test_and_set returns the old state of the lock, so we + have acquired it if it returns 0. */ + + if (!state->threaded) + locked = 1; + else + locked = __sync_lock_test_and_set (&state->lock_alloc, 1) == 0; + + if (locked) + { + backtrace_free_locked (state, addr, size); + + if (state->threaded) + __sync_lock_release (&state->lock_alloc); + } +} + +/* Grow VEC by SIZE bytes. */ + +void * +backtrace_vector_grow (struct backtrace_state *state,size_t size, + backtrace_error_callback error_callback, + void *data, struct backtrace_vector *vec) +{ + void *ret; + + if (size > vec->alc) + { + size_t pagesize; + size_t alc; + void *base; + + pagesize = getpagesize (); + alc = vec->size + size; + if (vec->size == 0) + alc = 16 * size; + else if (alc < pagesize) + { + alc *= 2; + if (alc > pagesize) + alc = pagesize; + } + else + { + alc *= 2; + alc = (alc + pagesize - 1) & ~ (pagesize - 1); + } + base = backtrace_alloc (state, alc, error_callback, data); + if (base == NULL) + return NULL; + if (vec->base != NULL) + { + memcpy (base, vec->base, vec->size); + backtrace_free (state, vec->base, vec->size + vec->alc, + error_callback, data); + } + vec->base = base; + vec->alc = alc - vec->size; + } + + ret = (char *) vec->base + vec->size; + vec->size += size; + vec->alc -= size; + return ret; +} + +/* Finish the current allocation on VEC. */ + +void * +backtrace_vector_finish ( + struct backtrace_state *state ATTRIBUTE_UNUSED, + struct backtrace_vector *vec, + backtrace_error_callback error_callback ATTRIBUTE_UNUSED, + void *data ATTRIBUTE_UNUSED) +{ + void *ret; + + ret = vec->base; + vec->base = (char *) vec->base + vec->size; + vec->size = 0; + return ret; +} + +/* Release any extra space allocated for VEC. */ + +int +backtrace_vector_release (struct backtrace_state *state, + struct backtrace_vector *vec, + backtrace_error_callback error_callback, + void *data) +{ + size_t size; + size_t alc; + size_t aligned; + + /* Make sure that the block that we free is aligned on an 8-byte + boundary. */ + size = vec->size; + alc = vec->alc; + aligned = (size + 7) & ~ (size_t) 7; + alc -= aligned - size; + + backtrace_free (state, (char *) vec->base + aligned, alc, + error_callback, data); + vec->alc = 0; + return 1; +} -- cgit v1.2.3-60-g2f50