X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=fd.c;h=8759d5099200c4f6c1b6c31e84b66da3372b5540;hp=c675aaffd4b99083d3ab0e26445574c2b87ad51b;hb=a9126f461792a84c760162ecb25100f1593d427d;hpb=40de1dd2fdbb054444d585aa70e2d50166a66e07 diff --git a/fd.c b/fd.c index c675aaff..8759d509 100644 --- a/fd.c +++ b/fd.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2006-2008 Andre Noll + * Copyright (C) 2006-2009 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ @@ -40,6 +40,45 @@ int write_all(int fd, const char *buf, size_t *len) return 1; } +/** + * Write a buffer to a non-blocking file descriptor. + * + * \param fd The file descriptor. + * \param buf the buffer to write. + * \param len the number of bytes of \a buf. + * \param max_bytes_per_write Do not write more than that many bytes at once. + * + * If \a max_bytes_per_write is non-zero, do not send more than that many bytes + * per write(). + * + * EAGAIN is not considered an error condition. For example CCID3 has a + * sending wait queue which fills up and is emptied asynchronously. The EAGAIN + * case means that there is currently no space in the wait queue, but this can + * change at any moment. + * + * \return Negative on errors, number of bytes written else. + */ +int write_nonblock(int fd, const char *buf, size_t len, + size_t max_bytes_per_write) +{ + size_t written = 0; + int ret = 0; + + while (written < len) { + size_t num = len - written; + + if (max_bytes_per_write && max_bytes_per_write < num) + num = max_bytes_per_write; + ret = write(fd, buf + written, num); + if (ret < 0 && errno == EAGAIN) + return written; + if (ret < 0) + return -ERRNO_TO_PARA_ERROR(errno); + written += ret; + } + return written; +} + /** * Check whether a file exists. * @@ -135,11 +174,7 @@ __must_check int mark_fd_nonblocking(int fd) */ void para_fd_set(int fd, fd_set *fds, int *max_fileno) { - - if (fd < 0 || fd >= FD_SETSIZE) { - PARA_EMERG_LOG("fatal: tried to add invalid fd %d\n", fd); - exit(EXIT_FAILURE); - } + assert(fd >= 0 && fd < FD_SETSIZE); #if 0 { int flags = fcntl(fd, F_GETFL); @@ -190,19 +225,26 @@ again: * \param flags Exactly one of MAP_SHARED and MAP_PRIVATE. * \param fd The file to mmap from. * \param offset Mmap start. + * \param map Result pointer. * - * \return This function either returns a valid pointer to the mapped area - * or calls exit() on errors. + * \return Standard. + * + * \sa mmap(2). */ -void *para_mmap(size_t length, int prot, int flags, int fd, off_t offset) +int para_mmap(size_t length, int prot, int flags, int fd, off_t offset, + void *map) { - void *ret = mmap(NULL, length, prot, flags, fd, offset); - if (ret != MAP_FAILED) - return ret; - PARA_EMERG_LOG("mmap failed: %s\n", strerror(errno)); - PARA_EMERG_LOG("length: %zu, flags: %d, fd: %d, offset: %zu\n", - length, flags, fd, (size_t)offset); - exit(EXIT_FAILURE); + void **m = map; + + errno = EINVAL; + if (!length) + goto err; + *m = mmap(NULL, length, prot, flags, fd, offset); + if (*m != MAP_FAILED) + return 1; +err: + *m = NULL; + return -ERRNO_TO_PARA_ERROR(errno); } /** @@ -363,17 +405,7 @@ int mmap_full_file(const char *path, int open_mode, void **map, goto out; } *size = file_status.st_size; - ret = -E_EMPTY; - PARA_DEBUG_LOG("%s: size %zu\n", path, *size); - if (!*size) - goto out; - *map = mmap(NULL, *size, mmap_prot, mmap_flags, fd, 0); - if (*map == MAP_FAILED) { - *map = NULL; - ret = -E_MMAP; - goto out; - } - ret = 1; + ret = para_mmap(*size, mmap_prot, mmap_flags, fd, 0, map); out: if (ret < 0 || !fd_ptr) close(fd);