X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmisc%2Fblock.c;h=efa4fce3271774de7be0585d5545d6dad3b53f51;hb=563338edada378178f1e61247b92b100fa55c97c;hp=40cdb2b1365ed9dc22ff2ba88580a20503a546b9;hpb=4903ec72c3a6422d409ea2ce8ce93463b1ff8e16;p=vlc diff --git a/src/misc/block.c b/src/misc/block.c index 40cdb2b136..efa4fce327 100644 --- a/src/misc/block.c +++ b/src/misc/block.c @@ -1,8 +1,8 @@ /***************************************************************************** * block.c: Data blocks management functions ***************************************************************************** - * Copyright (C) 2003-2004 VideoLAN - * $Id$ + * Copyright (C) 2003-2004 the VideoLAN team + * Copyright (C) 2007-2009 Rémi Denis-Courmont * * Authors: Laurent Aimar * @@ -18,323 +18,482 @@ * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA. + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ /***************************************************************************** * Preamble *****************************************************************************/ -#include -#include - -#include +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include +#include +#include +#include #include "vlc_block.h" -/* private */ +/** + * @section Block handling functions. + */ + +/** + * Internal state for heap block. + */ struct block_sys_t { - vlc_mutex_t lock; - - uint8_t *p_allocated_buffer; - int i_allocated_buffer; - - vlc_bool_t b_modify; /* has it been put in modified state */ - int i_duplicated; /* how many times has the content been - * duplicated */ - + block_t self; + size_t i_allocated_buffer; + uint8_t p_allocated_buffer[]; }; -static void BlockRelease( block_t *p_block ) +#ifndef NDEBUG +static void BlockNoRelease( block_t *b ) { - vlc_mutex_lock( &p_block->p_sys->lock ); - - p_block->p_sys->i_duplicated--; - if( p_block->p_sys->i_duplicated < 0 ) - { - vlc_mutex_unlock( &p_block->p_sys->lock ); - vlc_mutex_destroy( &p_block->p_sys->lock ); - free( p_block->p_sys->p_allocated_buffer ); - free( p_block->p_sys ); - free( p_block ); + fprintf( stderr, "block %p has no release callback! This is a bug!\n", b ); + abort(); +} +#endif - return; - } +void block_Init( block_t *restrict b, void *buf, size_t size ) +{ + /* Fill all fields to their default */ + b->p_next = NULL; + b->i_flags = 0; + b->i_pts = + b->i_dts = VLC_TS_INVALID; + b->i_length = 0; + b->i_rate = 0; + b->i_nb_samples = 0; + b->p_buffer = buf; + b->i_buffer = size; +#ifndef NDEBUG + b->pf_release = BlockNoRelease; +#endif +} - vlc_mutex_unlock( &p_block->p_sys->lock ); +static void BlockRelease( block_t *p_block ) +{ free( p_block ); } -static block_t *__BlockDupContent( block_t *p_block ) +static void BlockMetaCopy( block_t *restrict out, const block_t *in ) { - block_t *p_dup; - - p_dup = block_New( p_block->p_manager, p_block->i_buffer ); - memcpy( p_dup->p_buffer, p_block->p_buffer, p_block->i_buffer ); - p_dup->i_flags = p_block->i_flags; - p_dup->i_pts = p_block->i_pts; - p_dup->i_dts = p_block->i_dts; - p_dup->i_length = p_block->i_length; - p_dup->i_rate = p_block->i_rate; - - return p_dup; + out->p_next = in->p_next; + out->i_dts = in->i_dts; + out->i_pts = in->i_pts; + out->i_flags = in->i_flags; + out->i_length = in->i_length; + out->i_rate = in->i_rate; + out->i_nb_samples = in->i_nb_samples; } -static block_t *BlockModify( block_t *p_block, vlc_bool_t b_will_modify ) +/* Memory alignment (must be a multiple of sizeof(void*) and a power of two) */ +#define BLOCK_ALIGN 16 +/* Initial reserved header and footer size (must be multiple of alignment) */ +#define BLOCK_PADDING 32 +/* Maximum size of reserved footer before we release with realloc() */ +#define BLOCK_WASTE_SIZE 2048 + +block_t *block_Alloc( size_t i_size ) { - block_t *p_mod = p_block; /* by default */ + /* We do only one malloc + * TODO: bench if doing 2 malloc but keeping a pool of buffer is better + * 2 * BLOCK_PADDING -> pre + post padding + */ + block_sys_t *p_sys; + uint8_t *buf; - vlc_mutex_lock( &p_block->p_sys->lock ); +#define ALIGN(x) (((x) + BLOCK_ALIGN - 1) & ~(BLOCK_ALIGN - 1)) +#if 0 /*def HAVE_POSIX_MEMALIGN */ + /* posix_memalign(,16,) is much slower than malloc() on glibc. + * -- Courmisch, September 2009, glibc 2.5 & 2.9 */ + const size_t i_alloc = ALIGN(sizeof(*p_sys)) + (2 * BLOCK_PADDING) + + ALIGN(i_size); + void *ptr; - if( p_block->p_sys->b_modify == b_will_modify ) - { - vlc_mutex_unlock( &p_block->p_sys->lock ); - return p_block; - } + if( posix_memalign( &ptr, BLOCK_ALIGN, i_alloc ) ) + return NULL; - if( p_block->p_sys->i_duplicated == 0 ) - { - p_block->p_sys->b_modify = b_will_modify; - vlc_mutex_unlock( &p_block->p_sys->lock ); - return p_block; - } + p_sys = ptr; + buf = p_sys->p_allocated_buffer + (-sizeof(*p_sys) & (BLOCK_ALIGN - 1)); + +#else + const size_t i_alloc = sizeof(*p_sys) + BLOCK_ALIGN + (2 * BLOCK_PADDING) + + ALIGN(i_size); + p_sys = malloc( i_alloc ); + if( p_sys == NULL ) + return NULL; + + buf = (void *)ALIGN((uintptr_t)p_sys->p_allocated_buffer); - /* FIXME we could avoid that - * we just need to create a new p_sys with new mem FIXME */ - p_mod = __BlockDupContent( p_block ); - vlc_mutex_unlock( &p_block->p_sys->lock ); +#endif + buf += BLOCK_PADDING; - BlockRelease( p_block ); + block_Init( &p_sys->self, buf, i_size ); + p_sys->self.pf_release = BlockRelease; + /* Fill opaque data */ + p_sys->i_allocated_buffer = i_alloc - sizeof(*p_sys); - return p_mod; + return &p_sys->self; } -static block_t *BlockDuplicate( block_t *p_block ) +block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) { - block_t *p_dup; + block_sys_t *p_sys = (block_sys_t *)p_block; + size_t requested = i_prebody + i_body; - vlc_mutex_lock( &p_block->p_sys->lock ); - if( !p_block->p_sys->b_modify ) + /* Corner case: empty block requested */ + if( i_prebody <= 0 && i_body <= (size_t)(-i_prebody) ) { - p_block->p_sys->i_duplicated++; - vlc_mutex_unlock( &p_block->p_sys->lock ); - p_dup = block_NewEmpty(); - memcpy( p_dup, p_block, sizeof( block_t ) ); - p_dup->p_next = NULL; - return p_dup; + block_Release( p_block ); + return NULL; } - p_dup = __BlockDupContent( p_block ); - vlc_mutex_unlock( &p_block->p_sys->lock ); - return p_dup; -} + if( p_block->pf_release != BlockRelease ) + { + /* Special case when pf_release if overloaded + * TODO if used one day, then implement it in a smarter way */ + block_t *p_dup = block_Duplicate( p_block ); + block_Release( p_block ); + if( !p_dup ) + return NULL; -static block_t *BlockRealloc( block_t *p_block, int i_prebody, int i_body ) -{ - int i_buffer_size = i_prebody + i_body; + p_block = p_dup; + p_sys = (block_sys_t *)p_block; + } + + uint8_t *p_start = p_sys->p_allocated_buffer; + uint8_t *p_end = p_sys->p_allocated_buffer + p_sys->i_allocated_buffer; + + assert( p_block->p_buffer + p_block->i_buffer <= p_end ); + assert( p_block->p_buffer >= p_start ); + + /* Corner case: the current payload is discarded completely */ + if( i_prebody <= 0 && p_block->i_buffer <= (size_t)-i_prebody ) + p_block->i_buffer = 0; /* discard current payload */ + if( p_block->i_buffer == 0 ) + { + size_t available = p_end - p_start; - if( i_body < 0 || i_buffer_size <= 0 ) return NULL; + if( requested <= available ) + { /* Enough room: recycle buffer */ + size_t extra = available - requested; + + p_block->p_buffer = p_start + (extra / 2); + p_block->i_buffer = requested; + return p_block; + } + /* Not enough room: allocate a new buffer */ + block_t *p_rea = block_Alloc( requested ); + if( p_rea ) + BlockMetaCopy( p_rea, p_block ); + block_Release( p_block ); + return p_rea; + } - vlc_mutex_lock( &p_block->p_sys->lock ); + /* First, shrink payload */ - if( i_prebody < ( p_block->p_buffer - p_block->p_sys->p_allocated_buffer + - p_block->p_sys->i_allocated_buffer ) || - p_block->p_buffer - i_prebody > p_block->p_sys->p_allocated_buffer ) + /* Pull payload start */ + if( i_prebody < 0 ) { + assert( p_block->i_buffer >= (size_t)-i_prebody ); p_block->p_buffer -= i_prebody; p_block->i_buffer += i_prebody; + i_body += i_prebody; i_prebody = 0; } - if( p_block->p_buffer + i_body < p_block->p_sys->p_allocated_buffer + - p_block->p_sys->i_allocated_buffer ) + + /* Trim payload end */ + if( p_block->i_buffer > i_body ) + p_block->i_buffer = i_body; + + /* Second, reallocate the buffer if we lack space. This is done now to + * minimize the payload size for memory copy. */ + assert( i_prebody >= 0 ); + if( (size_t)(p_block->p_buffer - p_start) < (size_t)i_prebody + || (size_t)(p_end - p_block->p_buffer) < i_body ) { - p_block->i_buffer = i_buffer_size; - i_body = 0; + block_t *p_rea = block_Alloc( requested ); + if( p_rea ) + { + BlockMetaCopy( p_rea, p_block ); + p_rea->p_buffer += i_prebody; + p_rea->i_buffer -= i_prebody; + memcpy( p_rea->p_buffer, p_block->p_buffer, p_block->i_buffer ); + } + block_Release( p_block ); + if( p_rea == NULL ) + return NULL; + p_block = p_rea; } - - if( !i_body || !i_prebody ) + else + /* We have a very large reserved footer now? Release some of it. + * XXX it might not preserve the alignment of p_buffer */ + if( p_end - (p_block->p_buffer + i_body) > BLOCK_WASTE_SIZE ) { - block_t *p_rea = block_New( p_block->p_manager, i_buffer_size ); - - p_rea->i_dts = p_block->i_dts; - p_rea->i_pts = p_block->i_pts; - p_rea->i_flags = p_block->i_flags; - p_rea->i_length= p_block->i_length; - p_rea->i_rate = p_block->i_rate; + block_t *p_rea = block_Alloc( requested ); + if( p_rea ) + { + BlockMetaCopy( p_rea, p_block ); + p_rea->p_buffer += i_prebody; + p_rea->i_buffer -= i_prebody; + memcpy( p_rea->p_buffer, p_block->p_buffer, p_block->i_buffer ); + block_Release( p_block ); + p_block = p_rea; + } + } - memcpy( p_rea->p_buffer + i_prebody, p_block->p_buffer, - __MIN( p_block->i_buffer, p_rea->i_buffer - i_prebody ) ); + /* NOTE: p_start and p_end are corrupted from this point */ - vlc_mutex_unlock( &p_block->p_sys->lock ); - block_Release( p_block ); + /* Third, expand payload */ - return p_rea; + /* Push payload start */ + if( i_prebody > 0 ) + { + p_block->p_buffer -= i_prebody; + p_block->i_buffer += i_prebody; + i_body += i_prebody; + i_prebody = 0; } - vlc_mutex_unlock( &p_block->p_sys->lock ); + /* Expand payload to requested size */ + p_block->i_buffer = i_body; return p_block; } -/***************************************************************************** - * Standard block management - * - *****************************************************************************/ -/* to be used by other block management */ -block_t *block_NewEmpty( void ) -{ - block_t *p_block; - - p_block = malloc( sizeof( block_t ) ); - memset( p_block, 0, sizeof( block_t ) ); - p_block->p_next = NULL; - p_block->i_flags = 0; - p_block->i_pts = 0; - p_block->i_dts = 0; - p_block->i_length = 0; - p_block->i_rate = 0; - - p_block->i_buffer = 0; - p_block->p_buffer = NULL; +typedef struct +{ + block_t self; + void *mem; +} block_heap_t; - p_block->pf_release = NULL; - p_block->pf_duplicate = NULL; - p_block->pf_modify = NULL; - p_block->pf_realloc = NULL; +static void block_heap_Release (block_t *self) +{ + block_heap_t *block = (block_heap_t *)self; - p_block->p_manager = NULL; - p_block->p_sys = NULL; - return p_block; + free (block->mem); + free (block); } -block_t *__block_New( vlc_object_t *p_obj, int i_size ) +/** + * Creates a block from a heap allocation. + * This is provided by LibVLC so that manually heap-allocated blocks can safely + * be deallocated even after the origin plugin has been unloaded from memory. + * + * When block_Release() is called, VLC will free() the specified pointer. + * + * @param ptr base address of the heap allocation (will be free()'d) + * @param addr base address of the useful buffer data + * @param length bytes length of the useful buffer data + * @return NULL in case of error (ptr free()'d in that case), or a valid + * block_t pointer. + */ +block_t *block_heap_Alloc (void *ptr, void *addr, size_t length) { - block_t *p_block; - block_sys_t *p_sys; - - p_block = block_NewEmpty(); - - p_block->pf_release = BlockRelease; - p_block->pf_duplicate = BlockDuplicate; - p_block->pf_modify = BlockModify; - p_block->pf_realloc = BlockRealloc; + block_heap_t *block = malloc (sizeof (*block)); + if (block == NULL) + { + free (addr); + return NULL; + } - /* that should be ok (no comunication between multiple p_vlc) */ - p_block->p_manager = VLC_OBJECT( p_obj->p_vlc ); + block_Init (&block->self, (uint8_t *)addr, length); + block->self.pf_release = block_heap_Release; + block->mem = ptr; + return &block->self; +} - p_block->p_sys = p_sys = malloc( sizeof( block_sys_t ) ); - vlc_mutex_init( p_obj, &p_sys->lock ); +#ifdef HAVE_MMAP +# include - /* XXX align on 16 and add 32 prebuffer/posbuffer bytes */ - p_sys->i_allocated_buffer = i_size + 32 + 32 + 16; - p_sys->p_allocated_buffer = malloc( p_sys->i_allocated_buffer ); - p_block->i_buffer = i_size; - p_block->p_buffer = &p_sys->p_allocated_buffer[32+15-((long)p_sys->p_allocated_buffer % 16 )]; +typedef struct block_mmap_t +{ + block_t self; + void *base_addr; + size_t length; +} block_mmap_t; - p_sys->i_duplicated = 0; - p_sys->b_modify = VLC_TRUE; +static void block_mmap_Release (block_t *block) +{ + block_mmap_t *p_sys = (block_mmap_t *)block; - return p_block; + munmap (p_sys->base_addr, p_sys->length); + free (p_sys); } -void block_ChainAppend( block_t **pp_list, block_t *p_block ) +/** + * Creates a block from a virtual address memory mapping (mmap). + * This is provided by LibVLC so that mmap blocks can safely be deallocated + * even after the allocating plugin has been unloaded from memory. + * + * @param addr base address of the mapping (as returned by mmap) + * @param length length (bytes) of the mapping (as passed to mmap) + * @return NULL if addr is MAP_FAILED, or an error occurred (in the later + * case, munmap(addr, length) is invoked before returning). + */ +block_t *block_mmap_Alloc (void *addr, size_t length) { + if (addr == MAP_FAILED) + return NULL; - if( *pp_list == NULL ) + block_mmap_t *block = malloc (sizeof (*block)); + if (block == NULL) { - *pp_list = p_block; + munmap (addr, length); + return NULL; } - else - { - block_t *p = *pp_list; - while( p->p_next ) - { - p = p->p_next; - } - p->p_next = p_block; - } + block_Init (&block->self, (uint8_t *)addr, length); + block->self.pf_release = block_mmap_Release; + block->base_addr = addr; + block->length = length; + return &block->self; } - -void block_ChainRelease( block_t *p_block ) +#else +block_t *block_mmap_Alloc (void *addr, size_t length) { - while( p_block ) - { - block_t *p_next; - p_next = p_block->p_next; - p_block->pf_release( p_block ); - p_block = p_next; - } + (void)addr; (void)length; return NULL; } +#endif -int block_ChainExtract( block_t *p_list, void *p_data, int i_max ) -{ - block_t *b; - int i_total = 0; - uint8_t *p = p_data; - for( b = p_list; b != NULL; b = b->p_next ) - { - int i_copy; +#ifdef WIN32 +# include +#ifdef UNDER_CE +#define _get_osfhandle(a) ((long) (a)) +#endif - i_copy = __MIN( i_max, b->i_buffer ); - if( i_copy > 0 ) - { - memcpy( p, b->p_buffer, i_copy ); - i_max -= i_copy; - i_total += i_copy; - p += i_copy; - - if( i_max == 0 ) - { - return i_total; - } - } - } - return i_total; +static +ssize_t pread (int fd, void *buf, size_t count, off_t offset) +{ + HANDLE handle = (HANDLE)(intptr_t)_get_osfhandle (fd); + if (handle == INVALID_HANDLE_VALUE) + return -1; + + OVERLAPPED olap; olap.Offset = offset; olap.OffsetHigh = (offset >> 32); + DWORD written; + /* This braindead API will override the file pointer even if we specify + * an explicit read offset... So do not expect this to mix well with + * regular read() calls. */ + if (ReadFile (handle, buf, count, &written, &olap)) + return written; + return -1; } +#endif -block_t *block_ChainGather( block_t *p_list ) +/** + * Loads a file into a block of memory. If possible a private file mapping is + * created. Otherwise, the file is read normally. On 32-bits platforms, this + * function will not work for very large files, due to memory space + * constraints. Cancellation point. + * + * @param fd file descriptor to load from + * @return a new block with the file content at p_buffer, and file length at + * i_buffer (release it with block_Release()), or NULL upon error (see errno). + */ +block_t *block_File (int fd) { - int i_total = 0; - block_t *b, *g; - - if( p_list->p_next == NULL ) + size_t length; + struct stat st; + + /* First, get the file size */ + if (fstat (fd, &st)) + return NULL; + + /* st_size is meaningful for regular files, shared memory and typed memory. + * It's also meaning for symlinks, but that's not possible with fstat(). + * In other cases, it's undefined, and we should really not go further. */ +#ifndef S_TYPEISSHM +# define S_TYPEISSHM( buf ) (0) +#endif + if (S_ISDIR (st.st_mode)) { - /* only one, so no need */ - return p_list; + errno = EISDIR; + return NULL; + } + if (!S_ISREG (st.st_mode) && !S_TYPEISSHM (&st)) + { + errno = ESPIPE; + return NULL; } - for( b = p_list; b != NULL; b = b->p_next ) + /* Prevent an integer overflow in mmap() and malloc() */ + if (st.st_size >= SIZE_MAX) { - i_total += b->i_buffer; + errno = ENOMEM; + return NULL; } + length = (size_t)st.st_size; - g = block_New( p_list->p_manager, i_total ); - block_ChainExtract( p_list, g->p_buffer, g->i_buffer ); +#ifdef HAVE_MMAP + if (length > 0) + { + void *addr; - g->i_flags = p_list->i_flags; - g->i_pts = p_list->i_pts; - g->i_dts = p_list->i_dts; + addr = mmap (NULL, length, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0); + if (addr != MAP_FAILED) + return block_mmap_Alloc (addr, length); + } +#endif + + /* If mmap() is not implemented by the OS _or_ the filesystem... */ + block_t *block = block_Alloc (length); + if (block == NULL) + return NULL; + block_cleanup_push (block); - /* free p_list */ - block_ChainRelease( p_list ); - return g; + for (size_t i = 0; i < length;) + { + ssize_t len = pread (fd, block->p_buffer + i, length - i, i); + if (len == -1) + { + block_Release (block); + block = NULL; + break; + } + i += len; + } + vlc_cleanup_pop (); + return block; } -/***************************************************************************** - * block_fifo_t management - *****************************************************************************/ -block_fifo_t *__block_FifoNew( vlc_object_t *p_obj ) +/** + * @section Thread-safe block queue functions + */ + +/** + * Internal state for block queues + */ +struct block_fifo_t { - block_fifo_t *p_fifo; + vlc_mutex_t lock; /* fifo data lock */ + vlc_cond_t wait; /**< Wait for data */ + vlc_cond_t wait_room; /**< Wait for queue depth to shrink */ + + block_t *p_first; + block_t **pp_last; + size_t i_depth; + size_t i_size; + bool b_force_wake; +}; - p_fifo = malloc( sizeof( vlc_object_t ) ); - vlc_mutex_init( p_obj, &p_fifo->lock ); - vlc_cond_init( p_obj, &p_fifo->wait ); - p_fifo->i_depth = 0; +block_fifo_t *block_FifoNew( void ) +{ + block_fifo_t *p_fifo = malloc( sizeof( block_fifo_t ) ); + if( !p_fifo ) + return NULL; + + vlc_mutex_init( &p_fifo->lock ); + vlc_cond_init( &p_fifo->wait ); + vlc_cond_init( &p_fifo->wait_room ); p_fifo->p_first = NULL; p_fifo->pp_last = &p_fifo->p_first; + p_fifo->i_depth = p_fifo->i_size = 0; + p_fifo->b_force_wake = false; return p_fifo; } @@ -342,6 +501,7 @@ block_fifo_t *__block_FifoNew( vlc_object_t *p_obj ) void block_FifoRelease( block_fifo_t *p_fifo ) { block_FifoEmpty( p_fifo ); + vlc_cond_destroy( &p_fifo->wait_room ); vlc_cond_destroy( &p_fifo->wait ); vlc_mutex_destroy( &p_fifo->lock ); free( p_fifo ); @@ -349,91 +509,187 @@ void block_FifoRelease( block_fifo_t *p_fifo ) void block_FifoEmpty( block_fifo_t *p_fifo ) { - block_t *b; + block_t *block; vlc_mutex_lock( &p_fifo->lock ); - for( b = p_fifo->p_first; b != NULL; ) + block = p_fifo->p_first; + if (block != NULL) { - block_t *p_next; - - p_next = b->p_next; - block_Release( b ); - b = p_next; + p_fifo->i_depth = p_fifo->i_size = 0; + p_fifo->p_first = NULL; + p_fifo->pp_last = &p_fifo->p_first; } - - p_fifo->i_depth = 0; - p_fifo->p_first = NULL; - p_fifo->pp_last = &p_fifo->p_first; + vlc_cond_broadcast( &p_fifo->wait_room ); vlc_mutex_unlock( &p_fifo->lock ); + + while (block != NULL) + { + block_t *buf; + + buf = block->p_next; + block_Release (block); + block = buf; + } } -int block_FifoPut( block_fifo_t *p_fifo, block_t *p_block ) +/** + * Wait until the FIFO gets below a certain size (if needed). + * + * Note that if more than one thread writes to the FIFO, you cannot assume that + * the FIFO is actually below the requested size upon return (since another + * thread could have refilled it already). This is typically not an issue, as + * this function is meant for (relaxed) congestion control. + * + * This function may be a cancellation point and it is cancel-safe. + * + * @param fifo queue to wait on + * @param max_depth wait until the queue has no more than this many blocks + * (use SIZE_MAX to ignore this constraint) + * @param max_size wait until the queue has no more than this many bytes + * (use SIZE_MAX to ignore this constraint) + * @return nothing. + */ +void block_FifoPace (block_fifo_t *fifo, size_t max_depth, size_t max_size) { - int i_size = 0; - vlc_mutex_lock( &p_fifo->lock ); + vlc_testcancel (); - do + vlc_mutex_lock (&fifo->lock); + while ((fifo->i_depth > max_depth) || (fifo->i_size > max_size)) { - i_size += p_block->i_buffer; - - *p_fifo->pp_last = p_block; - p_fifo->pp_last = &p_block->p_next; - p_fifo->i_depth++; + mutex_cleanup_push (&fifo->lock); + vlc_cond_wait (&fifo->wait_room, &fifo->lock); + vlc_cleanup_pop (); + } + vlc_mutex_unlock (&fifo->lock); +} - p_block = p_block->p_next; +/** + * Immediately queue one block at the end of a FIFO. + * @param fifo queue + * @param block head of a block list to queue (may be NULL) + * @return total number of bytes appended to the queue + */ +size_t block_FifoPut( block_fifo_t *p_fifo, block_t *p_block ) +{ + size_t i_size = 0, i_depth = 0; + block_t *p_last; - } while( p_block ); + if (p_block == NULL) + return 0; + for (p_last = p_block; ; p_last = p_last->p_next) + { + i_size += p_last->i_buffer; + i_depth++; + if (!p_last->p_next) + break; + } - /* warn there is data in this fifo */ + vlc_mutex_lock (&p_fifo->lock); + *p_fifo->pp_last = p_block; + p_fifo->pp_last = &p_last->p_next; + p_fifo->i_depth += i_depth; + p_fifo->i_size += i_size; + /* We queued at least one block: wake up one read-waiting thread */ vlc_cond_signal( &p_fifo->wait ); vlc_mutex_unlock( &p_fifo->lock ); return i_size; } +void block_FifoWake( block_fifo_t *p_fifo ) +{ + vlc_mutex_lock( &p_fifo->lock ); + if( p_fifo->p_first == NULL ) + p_fifo->b_force_wake = true; + vlc_cond_broadcast( &p_fifo->wait ); + vlc_mutex_unlock( &p_fifo->lock ); +} + +/** + * Dequeue the first block from the FIFO. If necessary, wait until there is + * one block in the queue. This function is (always) cancellation point. + * + * @return a valid block, or NULL if block_FifoWake() was called. + */ block_t *block_FifoGet( block_fifo_t *p_fifo ) { block_t *b; + vlc_testcancel( ); + vlc_mutex_lock( &p_fifo->lock ); + mutex_cleanup_push( &p_fifo->lock ); - if( p_fifo->p_first == NULL ) - { + /* Remember vlc_cond_wait() may cause spurious wakeups + * (on both Win32 and POSIX) */ + while( ( p_fifo->p_first == NULL ) && !p_fifo->b_force_wake ) vlc_cond_wait( &p_fifo->wait, &p_fifo->lock ); - } + vlc_cleanup_pop(); b = p_fifo->p_first; + p_fifo->b_force_wake = false; + if( b == NULL ) + { + /* Forced wakeup */ + vlc_mutex_unlock( &p_fifo->lock ); + return NULL; + } + p_fifo->p_first = b->p_next; p_fifo->i_depth--; + p_fifo->i_size -= b->i_buffer; if( p_fifo->p_first == NULL ) { p_fifo->pp_last = &p_fifo->p_first; } + /* We don't know how many threads can queue new packets now. */ + vlc_cond_broadcast( &p_fifo->wait_room ); vlc_mutex_unlock( &p_fifo->lock ); b->p_next = NULL; - return( b ); + return b; } +/** + * Peeks the first block in the FIFO. + * If necessary, wait until there is one block. + * This function is (always) a cancellation point. + * + * @warning This function leaves the block in the FIFO. + * You need to protect against concurrent threads who could dequeue the block. + * Preferrably, there should be only one thread reading from the FIFO. + * + * @return a valid block. + */ block_t *block_FifoShow( block_fifo_t *p_fifo ) { block_t *b; + vlc_testcancel( ); + vlc_mutex_lock( &p_fifo->lock ); + mutex_cleanup_push( &p_fifo->lock ); - if( p_fifo->p_first == NULL ) - { + while( p_fifo->p_first == NULL ) vlc_cond_wait( &p_fifo->wait, &p_fifo->lock ); - } b = p_fifo->p_first; - vlc_mutex_unlock( &p_fifo->lock ); - - return( b ); + vlc_cleanup_run (); + return b; +} +/* FIXME: not thread-safe */ +size_t block_FifoSize( const block_fifo_t *p_fifo ) +{ + return p_fifo->i_size; } +/* FIXME: not thread-safe */ +size_t block_FifoCount( const block_fifo_t *p_fifo ) +{ + return p_fifo->i_depth; +}