X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmisc%2Fblock.c;h=a757e3cf2d487753602ca57282b3e905d2940095;hb=54b65bedc9a2abe2461f650c0d40b387f0839174;hp=8699261a7f8e6f8c7fec06f645d33637a002c673;hpb=85b29bdc288a1573d43bd524908be5748a9b3640;p=vlc diff --git a/src/misc/block.c b/src/misc/block.c index 8699261a7f..a757e3cf2d 100644 --- a/src/misc/block.c +++ b/src/misc/block.c @@ -1,7 +1,7 @@ /***************************************************************************** * block.c: Data blocks management functions ***************************************************************************** - * Copyright (C) 2003-2004 VideoLAN (Centrale Réseaux) and its contributors + * Copyright (C) 2003-2004 the VideoLAN team * $Id$ * * Authors: Laurent Aimar @@ -18,15 +18,18 @@ * * 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 +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif -#include +#include +#include #include "vlc_block.h" /***************************************************************************** @@ -35,127 +38,330 @@ /* private */ struct block_sys_t { - uint8_t *p_allocated_buffer; - int i_allocated_buffer; + block_t self; + size_t i_allocated_buffer; + uint8_t p_allocated_buffer[0]; }; +#ifndef NDEBUG +static void BlockNoRelease( block_t *b ) +{ + fprintf( stderr, "block %p has no release callback! This is a bug!\n", b ); + abort(); +} +#endif + +void block_Init( block_t *restrict b, void *buf, size_t size ) +{ + /* Fill all fields to their default */ + b->p_next = b->p_prev = NULL; + b->i_flags = 0; + b->i_pts = b->i_dts = b->i_length = 0; + b->i_rate = 0; + b->p_buffer = buf; + b->i_buffer = size; +#ifndef NDEBUG + b->pf_release = BlockNoRelease; +#endif +} + +static void BlockRelease( block_t *p_block ) +{ + free( p_block ); +} + +/* Memory alignment */ +#define BLOCK_ALIGN 16 +/* Initial size of reserved header and footer */ #define BLOCK_PADDING_SIZE 32 -static void BlockRelease( block_t * ); +/* Maximum size of reserved footer before we release with realloc() */ +#define BLOCK_WASTE_SIZE 2048 -block_t *__block_New( vlc_object_t *p_obj, int i_size ) +block_t *block_Alloc( size_t i_size ) { /* We do only one malloc - * TODO bench if doing 2 malloc but keeping a pool of buffer is better + * TODO: bench if doing 2 malloc but keeping a pool of buffer is better + * TODO: use memalign * 16 -> align on 16 * 2 * BLOCK_PADDING_SIZE -> pre + post padding */ - block_sys_t *p_sys; - const int i_alloc = i_size + 2 * BLOCK_PADDING_SIZE + 16; - block_t *p_block = - malloc( sizeof( block_t ) + sizeof( block_sys_t ) + i_alloc ); + const size_t i_alloc = i_size + 2 * BLOCK_PADDING_SIZE + BLOCK_ALIGN; + block_sys_t *p_sys = malloc( sizeof( *p_sys ) + i_alloc ); - if( p_block == NULL ) return NULL; + if( p_sys == NULL ) + return NULL; /* Fill opaque data */ - p_sys = (block_sys_t*)( (uint8_t*)p_block + sizeof( block_t ) ); p_sys->i_allocated_buffer = i_alloc; - p_sys->p_allocated_buffer = (uint8_t*)p_block + sizeof( block_t ) + - sizeof( block_sys_t ); - - /* Fill all fields */ - 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 = i_size; - p_block->p_buffer = - &p_sys->p_allocated_buffer[BLOCK_PADDING_SIZE + - 16 - ((uintptr_t)p_sys->p_allocated_buffer % 16 )]; - p_block->pf_release = BlockRelease; - - /* Is ok, as no comunication between p_vlc */ - p_block->p_manager = VLC_OBJECT( p_obj->p_vlc ); - p_block->p_sys = p_sys; - return p_block; + block_Init( &p_sys->self, p_sys->p_allocated_buffer + BLOCK_PADDING_SIZE + + BLOCK_ALIGN + - ((uintptr_t)p_sys->p_allocated_buffer % BLOCK_ALIGN), + i_size ); + p_sys->self.pf_release = BlockRelease; + + return &p_sys->self; } -block_t *block_Realloc( block_t *p_block, int i_prebody, int i_body ) +block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) { - int i_buffer_size; + block_sys_t *p_sys = (block_sys_t *)p_block; + ssize_t i_buffer_size = i_prebody + i_body; + + if( i_buffer_size <= 0 ) + { + block_Release( p_block ); + return NULL; + } if( p_block->pf_release != BlockRelease ) { /* Special case when pf_release if overloaded - * TODO if used one day, them implement it in a smarter way */ + * 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; p_block = p_dup; } - i_buffer_size = i_prebody + i_body; - - if( i_body < 0 || i_buffer_size <= 0 ) return NULL; - - if( p_block->p_buffer - i_prebody > p_block->p_sys->p_allocated_buffer && - p_block->p_buffer - i_prebody < p_block->p_sys->p_allocated_buffer + - p_block->p_sys->i_allocated_buffer ) + /* Adjust reserved header if there is enough room */ + if( p_block->p_buffer - i_prebody > p_sys->p_allocated_buffer && + p_block->p_buffer - i_prebody < p_sys->p_allocated_buffer + + p_sys->i_allocated_buffer ) { p_block->p_buffer -= i_prebody; p_block->i_buffer += 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 ) + + /* Adjust payload size if there is enough room */ + if( p_block->p_buffer + i_body < p_sys->p_allocated_buffer + + p_sys->i_allocated_buffer ) { p_block->i_buffer = i_buffer_size; i_body = 0; } + /* Not enough room, reallocate the buffer */ if( i_body > 0 || i_prebody > 0 ) { - 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; - p_rea->i_samples = p_block->i_samples; - - memcpy( p_rea->p_buffer + i_prebody, p_block->p_buffer, - __MIN( p_block->i_buffer, p_rea->i_buffer - i_prebody ) ); + /* FIXME: this is really dumb, we should use realloc() */ + block_t *p_rea = block_New( NULL, i_buffer_size ); + + if( p_rea ) + { + 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; + p_rea->i_samples = p_block->i_samples; + + memcpy( p_rea->p_buffer + i_prebody, p_block->p_buffer, + __MIN( p_block->i_buffer, p_rea->i_buffer - i_prebody ) ); + } block_Release( p_block ); return p_rea; } + /* We have a very large reserved footer now? Release some of it. */ + if ((p_sys->p_allocated_buffer + p_sys->i_allocated_buffer) - + (p_block->p_buffer + p_block->i_buffer) > BLOCK_WASTE_SIZE) + { + const size_t news = p_block->i_buffer + 2 * BLOCK_PADDING_SIZE + 16; + block_sys_t *newb = realloc (p_sys, sizeof (*p_sys) + news); + + if (newb != NULL) + { + p_sys = newb; + p_sys->i_allocated_buffer = news; + p_block = &p_sys->self; + p_block->p_buffer = p_sys->p_allocated_buffer + BLOCK_PADDING_SIZE + + BLOCK_ALIGN + - ((uintptr_t)p_sys->p_allocated_buffer % BLOCK_ALIGN); + } + } + return p_block; } -static void BlockRelease( block_t *p_block ) +#ifdef HAVE_MMAP +# include + +typedef struct block_mmap_t { - free( p_block ); + block_t self; + void *base_addr; + size_t length; +} block_mmap_t; + +static void block_mmap_Release (block_t *block) +{ + block_mmap_t *p_sys = (block_mmap_t *)block; + + munmap (p_sys->base_addr, p_sys->length); + free (p_sys); +} + +/** + * 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; + + block_mmap_t *block = malloc (sizeof (*block)); + if (block == NULL) + { + munmap (addr, length); + return NULL; + } + + 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; +} +#else +block_t *block_mmap_Alloc (void *addr, size_t length) +{ + (void)addr; (void)length; return NULL; } +#endif +#ifdef WIN32 +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 = { .Offset = offset, .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 + +/** + * 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. + * + * @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) +{ + 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)) + { + errno = EISDIR; + return NULL; + } + if (!S_ISREG (st.st_mode) && !S_TYPEISSHM (&st)) + { + errno = ESPIPE; + return NULL; + } + + /* Prevent an integer overflow in mmap() and malloc() */ + if (st.st_size >= SIZE_MAX) + { + errno = ENOMEM; + return NULL; + } + length = (size_t)st.st_size; + +#ifdef HAVE_MMAP + if (length > 0) + { + void *addr; + + 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; + + 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); + return NULL; + } + i += len; + } + return block; +} + /***************************************************************************** * block_fifo_t management *****************************************************************************/ -block_fifo_t *__block_FifoNew( vlc_object_t *p_obj ) +struct block_fifo_t { - block_fifo_t *p_fifo; + vlc_mutex_t lock; /* fifo data lock */ + vlc_cond_t wait; /* fifo data conditional variable */ + + 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 = p_fifo->i_size = 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( NULL, &p_fifo->wait ); 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; } @@ -188,9 +394,9 @@ void block_FifoEmpty( block_fifo_t *p_fifo ) vlc_mutex_unlock( &p_fifo->lock ); } -int block_FifoPut( block_fifo_t *p_fifo, block_t *p_block ) +size_t block_FifoPut( block_fifo_t *p_fifo, block_t *p_block ) { - int i_size = 0; + size_t i_size = 0; vlc_mutex_lock( &p_fifo->lock ); do @@ -213,22 +419,38 @@ int block_FifoPut( block_fifo_t *p_fifo, block_t *p_block ) 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_signal( &p_fifo->wait ); + vlc_mutex_unlock( &p_fifo->lock ); +} + block_t *block_FifoGet( block_fifo_t *p_fifo ) { block_t *b; vlc_mutex_lock( &p_fifo->lock ); - /* We do a while here because there is a race condition in the - * win32 implementation of vlc_cond_wait() (We can't be sure the fifo - * hasn't been emptied again since we were signaled). */ - while( 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 ); } 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; @@ -260,6 +482,14 @@ block_t *block_FifoShow( block_fifo_t *p_fifo ) vlc_mutex_unlock( &p_fifo->lock ); return( b ); +} +size_t block_FifoSize( const block_fifo_t *p_fifo ) +{ + return p_fifo->i_size; } +size_t block_FifoCount( const block_fifo_t *p_fifo ) +{ + return p_fifo->i_depth; +}