X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmisc%2Fblock.c;h=a757e3cf2d487753602ca57282b3e905d2940095;hb=0d8adc76dbf01e54ef043a07a623982a7fa9a426;hp=31a001b9b2dde231bc516a3892caca9d08cf931a;hpb=99fab9089e9e1709d9c3a4bc5ced0c137ac59134;p=vlc diff --git a/src/misc/block.c b/src/misc/block.c index 31a001b9b2..a757e3cf2d 100644 --- a/src/misc/block.c +++ b/src/misc/block.c @@ -28,7 +28,8 @@ # include "config.h" #endif -#include +#include +#include #include "vlc_block.h" /***************************************************************************** @@ -69,16 +70,22 @@ 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 +/* Maximum size of reserved footer before we release with realloc() */ +#define BLOCK_WASTE_SIZE 2048 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 */ - const size_t i_alloc = i_size + 2 * BLOCK_PADDING_SIZE + 16; + 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_sys == NULL ) @@ -88,7 +95,9 @@ block_t *block_Alloc( size_t i_size ) p_sys->i_allocated_buffer = i_alloc; block_Init( &p_sys->self, p_sys->p_allocated_buffer + BLOCK_PADDING_SIZE - + 16 - ((uintptr_t)p_sys->p_allocated_buffer % 16 ), i_size ); + + BLOCK_ALIGN + - ((uintptr_t)p_sys->p_allocated_buffer % BLOCK_ALIGN), + i_size ); p_sys->self.pf_release = BlockRelease; return &p_sys->self; @@ -97,12 +106,18 @@ block_t *block_Alloc( size_t i_size ) block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) { block_sys_t *p_sys = (block_sys_t *)p_block; - ssize_t i_buffer_size; + 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 ) @@ -111,14 +126,7 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) p_block = p_dup; } - i_buffer_size = i_prebody + i_body; - - if( i_buffer_size <= 0 ) - { - block_Release( p_block ); - return NULL; - } - + /* 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 ) @@ -127,6 +135,8 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) p_block->i_buffer += i_prebody; i_prebody = 0; } + + /* 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 ) { @@ -134,8 +144,10 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) i_body = 0; } + /* Not enough room, reallocate the buffer */ if( i_body > 0 || i_prebody > 0 ) { + /* FIXME: this is really dumb, we should use realloc() */ block_t *p_rea = block_New( NULL, i_buffer_size ); if( p_rea ) @@ -156,6 +168,24 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) 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; } @@ -177,6 +207,16 @@ static void block_mmap_Release (block_t *block) 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) @@ -195,8 +235,106 @@ block_t *block_mmap_Alloc (void *addr, size_t length) 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 *****************************************************************************/ @@ -209,21 +347,21 @@ struct block_fifo_t block_t **pp_last; size_t i_depth; size_t i_size; - vlc_bool_t b_force_wake; + bool b_force_wake; }; -block_fifo_t *__block_FifoNew( vlc_object_t *p_obj ) +block_fifo_t *block_FifoNew( void ) { - block_fifo_t *p_fifo; + block_fifo_t *p_fifo = malloc( sizeof( block_fifo_t ) ); + if( !p_fifo ) + return NULL; - p_fifo = malloc( sizeof( block_fifo_t ) ); - if( !p_fifo ) return NULL; - vlc_mutex_init( p_obj, &p_fifo->lock ); - vlc_cond_init( p_obj, &p_fifo->wait ); + 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 = VLC_FALSE; + p_fifo->b_force_wake = false; return p_fifo; } @@ -285,7 +423,7 @@ 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 = VLC_TRUE; + p_fifo->b_force_wake = true; vlc_cond_signal( &p_fifo->wait ); vlc_mutex_unlock( &p_fifo->lock ); } @@ -305,7 +443,7 @@ block_t *block_FifoGet( block_fifo_t *p_fifo ) b = p_fifo->p_first; - p_fifo->b_force_wake = VLC_FALSE; + p_fifo->b_force_wake = false; if( b == NULL ) { /* Forced wakeup */