mirror of
https://libwebsockets.org/repo/libwebsockets
synced 2024-11-24 01:39:33 +00:00
c9731c5f17
This is a huge patch that should be a global NOP. For unix type platforms it enables -Wconversion to issue warnings (-> error) for all automatic casts that seem less than ideal but are normally concealed by the toolchain. This is things like passing an int to a size_t argument. Once enabled, I went through all args on my default build (which build most things) and tried to make the removed default cast explicit. With that approach it neither change nor bloat the code, since it compiles to whatever it was doing before, just with the casts made explicit... in a few cases I changed some length args from int to size_t but largely left the causes alone. From now on, new code that is relying on less than ideal casting will complain and nudge me to improve it by warnings.
219 lines
5.6 KiB
C
219 lines
5.6 KiB
C
/*
|
|
* libwebsockets - small server side websockets and web server implementation
|
|
*
|
|
* Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to
|
|
* deal in the Software without restriction, including without limitation the
|
|
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
|
|
* sell copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
* IN THE SOFTWARE.
|
|
*/
|
|
|
|
#if !defined(LWS_PLAT_OPTEE) && !defined(OPTEE_DEV_KIT)
|
|
|
|
#include "private-lib-core.h"
|
|
#include "private-lib-misc-lwsac.h"
|
|
|
|
/*
|
|
* Helper for caching a file in memory in a lac, but also to check at intervals
|
|
* no less than 5s if the file is still fresh.
|
|
*
|
|
* Set *cache to NULL the first time before calling.
|
|
*
|
|
* You should call this each time before using the cache... if it's
|
|
*
|
|
* - less than 5s since the last freshness check, and
|
|
* - the file is already in memory
|
|
*
|
|
* it just returns with *cache left alone; this costs very little. You should
|
|
* call `lwsac_use_cached_file_start()` and `lwsac_use_cached_file_end()`
|
|
* to lock the cache against deletion while you are using it.
|
|
*
|
|
* If it's
|
|
*
|
|
* - at least 5s since the last freshness check, and
|
|
* - the file timestamp has changed
|
|
*
|
|
* then
|
|
*
|
|
* - the file is reloaded into a new lac and *cache set to that
|
|
*
|
|
* - the old cache lac, if any, is detached (so it will be freed when its
|
|
* reference count reaches zero, or immediately if nobody has it)
|
|
*
|
|
* Note the call can fail due to OOM or filesystem issue at any time.
|
|
*
|
|
*
|
|
* After the LAC header there is stored a `struct cached_file_info` and then
|
|
* the raw file contents. *
|
|
*
|
|
* [LAC header]
|
|
* [struct cached_file_info]
|
|
* [file contents] <--- *cache is set to here
|
|
*
|
|
* The api returns a lwsac_cached_file_t type offset to point to the file
|
|
* contents. Helpers for reference counting and freeing are also provided
|
|
* that take that type and know how to correct it back to operate on the LAC.
|
|
*/
|
|
|
|
#define cache_file_to_lac(c) ((struct lwsac *)((char *)c - \
|
|
sizeof(struct cached_file_info) - \
|
|
sizeof(struct lwsac_head) - \
|
|
sizeof(struct lwsac)))
|
|
|
|
void
|
|
lwsac_use_cached_file_start(lwsac_cached_file_t cache)
|
|
{
|
|
struct lwsac *lac = cache_file_to_lac(cache);
|
|
struct lwsac_head *lachead = (struct lwsac_head *)&lac->head[1];
|
|
|
|
lachead->refcount++;
|
|
// lwsl_debug("%s: html refcount: %d\n", __func__, lachead->refcount);
|
|
}
|
|
|
|
void
|
|
lwsac_use_cached_file_end(lwsac_cached_file_t *cache)
|
|
{
|
|
struct lwsac *lac;
|
|
struct lwsac_head *lachead;
|
|
|
|
if (!cache || !*cache)
|
|
return;
|
|
|
|
lac = cache_file_to_lac(*cache);
|
|
lachead = (struct lwsac_head *)&lac->head[1];
|
|
|
|
if (!lachead->refcount)
|
|
lwsl_err("%s: html refcount zero on entry\n", __func__);
|
|
|
|
if (lachead->refcount && !--lachead->refcount && lachead->detached) {
|
|
*cache = NULL; /* not usable any more */
|
|
lwsac_free(&lac);
|
|
}
|
|
}
|
|
|
|
void
|
|
lwsac_use_cached_file_detach(lwsac_cached_file_t *cache)
|
|
{
|
|
struct lwsac *lac = cache_file_to_lac(*cache);
|
|
struct lwsac_head *lachead = NULL;
|
|
|
|
if (lac) {
|
|
lachead = (struct lwsac_head *)&lac->head[1];
|
|
|
|
lachead->detached = 1;
|
|
if (lachead->refcount)
|
|
return;
|
|
}
|
|
|
|
*cache = NULL;
|
|
lwsac_free(&lac);
|
|
}
|
|
|
|
int
|
|
lwsac_cached_file(const char *filepath, lwsac_cached_file_t *cache, size_t *len)
|
|
{
|
|
struct cached_file_info *info = NULL;
|
|
lwsac_cached_file_t old = *cache;
|
|
struct lwsac *lac = NULL;
|
|
time_t t = time(NULL);
|
|
unsigned char *a;
|
|
struct stat s;
|
|
size_t all;
|
|
ssize_t rd;
|
|
int fd;
|
|
|
|
if (old) { /* we already have a cached copy of it */
|
|
|
|
info = (struct cached_file_info *)((*cache) - sizeof(*info));
|
|
|
|
if (t - info->last_confirm < 5)
|
|
/* we checked it as fresh less than 5s ago, use old */
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* ...it's been 5s, we should check again on the filesystem
|
|
* that the file hasn't changed
|
|
*/
|
|
|
|
fd = open(filepath, O_RDONLY);
|
|
if (fd < 0) {
|
|
lwsl_err("%s: cannot open %s\n", __func__, filepath);
|
|
|
|
return 1;
|
|
}
|
|
|
|
if (fstat(fd, &s)) {
|
|
lwsl_err("%s: cannot stat %s\n", __func__, filepath);
|
|
|
|
goto bail;
|
|
}
|
|
|
|
if (old && s.st_mtime == info->s.st_mtime) {
|
|
/* it still seems to be the same as our cached one */
|
|
info->last_confirm = t;
|
|
|
|
close(fd);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* we either didn't cache it yet, or it has changed since we cached
|
|
* it... reload in a new lac and then detach the old lac.
|
|
*/
|
|
|
|
all = sizeof(*info) + (unsigned long)s.st_size + 2;
|
|
|
|
info = lwsac_use(&lac, all, all);
|
|
if (!info)
|
|
goto bail;
|
|
|
|
info->s = s;
|
|
info->last_confirm = t;
|
|
|
|
a = (unsigned char *)(info + 1);
|
|
|
|
*len = (unsigned long)s.st_size;
|
|
a[s.st_size] = '\0';
|
|
|
|
rd = read(fd, a, (unsigned long)s.st_size);
|
|
if (rd != s.st_size) {
|
|
lwsl_err("%s: cannot read %s (%d)\n", __func__, filepath,
|
|
(int)rd);
|
|
goto bail1;
|
|
}
|
|
|
|
close(fd);
|
|
|
|
*cache = (lwsac_cached_file_t)a;
|
|
if (old)
|
|
lwsac_use_cached_file_detach(&old);
|
|
|
|
return 0;
|
|
|
|
bail1:
|
|
lwsac_free(&lac);
|
|
|
|
bail:
|
|
close(fd);
|
|
|
|
return 1;
|
|
}
|
|
|
|
#endif
|