rdelaage
/
httpdirfs
mirror of https://github.com/fangfufu/httpdirfs.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

fixed Cache_bgdl() 

- Cache_bgdl() used to corrupt the cache file
This commit is contained in:
Fufu Fang 2019-09-02 09:04:20 +01:00
parent e06ea6dc06
commit 9e3e4747ae
No known key found for this signature in database
GPG Key ID: 0F6BB5EF6F8BB729
2 changed files with 36 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

63
src/cache.c
View File

@ -447,6 +447,7 @@ static long Data_write(Cache *cf, const uint8_t *buf, off_t len,
"Data_write(): fwrite(): encountered error!\n");
}
}
#ifdef CACHE_LOCK_DEBUG
fprintf(stderr, "Data_write(): thread %lu: unlocking seek_lock;\n",
pthread_self());
@ -558,12 +559,10 @@ static int Cache_exist(const char *fn)
char *datafn = path_append(DATA_DIR, fn);
if (access(metafn, F_OK)) {
// fprintf(stderr, "Cache_exist(): access(): %s\n", strerror(errno));
meta_exists = 0;
}
if (access(datafn, F_OK)) {
// fprintf(stderr, "Cache_exist(): access(): %s\n", strerror(errno));
data_exists = 0;
}
@ -849,6 +848,15 @@ void Cache_close(Cache *cf)
return;
}
#ifdef CACHE_LOCK_DEBUG
fprintf(stderr,
"Cache_close(): thread %lu: locking and unlocking bgt_lock;\n",
pthread_self());
#endif
PTHREAD_MUTEX_LOCK(&cf->bgt_lock);
PTHREAD_MUTEX_UNLOCK(&cf->bgt_lock);
#ifdef CACHE_LOCK_DEBUG
fprintf(stderr, "Cache_close(): thread %lu: unlocking cf_lock;\n",
pthread_self());
@ -883,6 +891,7 @@ static int Seg_exist(Cache *cf, off_t offset)
off_t byte = offset / cf->blksz;
return cf->seg[byte];
}
/**
* \brief Set the existence of a segment
* \param[in] cf the cache in-memory data structure
@ -911,13 +920,13 @@ static void *Cache_bgdl(void *arg)
#endif
PTHREAD_MUTEX_LOCK(&cf->w_lock);
uint8_t *recv_buf = calloc(cf->blksz, sizeof(uint8_t));
fprintf(stderr, "Cache_bgdl(): thread %lu:", pthread_self());
fprintf(stderr, "Cache_bgdl(): thread %lu: ", pthread_self());
long recv = path_download(cf->path, (char *) recv_buf, cf->blksz,
cf->next_offset);
if ( (recv == cf->blksz) ||
(cf->next_offset == (cf->content_length / cf->blksz * cf->blksz)) )
{
Data_write(cf, recv_buf, cf->blksz, cf->next_offset);
Data_write(cf, recv_buf, recv, cf->next_offset);
Seg_set(cf, cf->next_offset, 1);
} else {
fprintf(stderr,
@ -938,15 +947,9 @@ static void *Cache_bgdl(void *arg)
pthread_exit(NULL);
}
long Cache_read(Cache *cf, char *output_buf, off_t len, off_t offset)
long Cache_read(Cache *cf, char * const output_buf, const off_t len,
const off_t offset)
{
size_t start = offset;
size_t end = start + len;
char range_str[64];
snprintf(range_str, sizeof(range_str), "%lu-%lu", start, end);
fprintf(stderr, "Cache_read(): thread %lu: %s, %s;\n", pthread_self(),
cf->path, range_str);
long send;
off_t dl_offset = offset / cf->blksz * cf->blksz;
@ -955,12 +958,11 @@ long Cache_read(Cache *cf, char *output_buf, off_t len, off_t offset)
send = Data_read(cf, (uint8_t *) output_buf, len, offset);
goto bgdl;
} else {
/* Wait for any other download thread to finish*/
#ifdef CACHE_LOCK_DEBUG
fprintf(stderr, "Cache_read(): thread %lu: locking w_lock;\n",
pthread_self());
#endif
/* Wait for any other download thread to finish*/
PTHREAD_MUTEX_LOCK(&cf->w_lock);
if (Seg_exist(cf, offset)) {
/* The segment now exists - it was downloaded by another
@ -978,39 +980,41 @@ long Cache_read(Cache *cf, char *output_buf, off_t len, off_t offset)
/* ------------------------Download the segment -------------------------*/
uint8_t *recv_buf = calloc(cf->blksz, sizeof(uint8_t));
fprintf(stderr, "Cache_read(): ");
fprintf(stderr, "Cache_read(): thread %lu: ", pthread_self());
long recv = path_download(cf->path, (char *) recv_buf, cf->blksz,
dl_offset);
if (recv < len) {
send = recv;
} else {
send = len;
}
memmove(output_buf, recv_buf + (offset - dl_offset), send);
/*
* check if we have received enough data
* send it off, then write it to the disk
*
* Condition 1: received the exact amount as the segment size.
* Condition 2: offset is the last segment
*/
* check if we have received enough data, write it to the disk
*
* Condition 1: received the exact amount as the segment size.
* Condition 2: offset is the last segment
*/
if ( (recv == cf->blksz) ||
(dl_offset == (cf->content_length / cf->blksz * cf->blksz)) )
{
memmove(output_buf, recv_buf + (offset - dl_offset), len);
send = len;
Data_write(cf, recv_buf, cf->blksz, dl_offset);
Data_write(cf, recv_buf, recv, dl_offset);
Seg_set(cf, dl_offset, 1);
} else {
memmove(output_buf, recv_buf + (offset - dl_offset), recv);
send = recv;
fprintf(stderr,
"Cache_read(): received %ld, possible network error.\n", recv);
}
free(recv_buf);
#ifdef CACHE_LOCK_DEBUG
fprintf(stderr, "Cache_read(): thread %lu: unlocking w_lock;\n",
pthread_self());
#endif
PTHREAD_MUTEX_UNLOCK(&cf->w_lock);
PTHREAD_MUTEX_UNLOCK(&cf->w_lock);
/* -----------Download the next segment in background -------------------*/
bgdl:
cf->next_offset = round_div(offset, cf->blksz) * cf->blksz;
if ( (cf->next_offset > dl_offset) &&
!Seg_exist(cf, cf->next_offset) &&
cf->next_offset < cf->content_length ){
@ -1020,7 +1024,8 @@ long Cache_read(Cache *cf, char *output_buf, off_t len, off_t offset)
fprintf(stderr, "Cache_read(): thread %lu: trylocked bgt_lock;\n",
pthread_self());
#endif
if (pthread_create(&cf->bgt, NULL, Cache_bgdl, cf)) {
cf->next_offset = round_div(offset, cf->blksz) * cf->blksz;
if (pthread_create(&cf->bgt, NULL, Cache_bgdl, cf)) {
fprintf(stderr,
"Cache_read(): Error creating background download thread\n"
);

4
src/cache.h
View File

@ -140,6 +140,6 @@ void Cache_delete(const char *fn);
* \return the length of the segment the cache system managed to obtain.
* \note Called by fs_read(), verified to be working
*/
long Cache_read(Cache *cf, char *output_buf, off_t len, off_t offset);
long Cache_read(Cache *cf, char * const output_buf, const off_t len,
const off_t offset);
#endif