diff options
Diffstat (limited to 'sysdeps/posix/readv.c')
| -rw-r--r-- | sysdeps/posix/readv.c | 40 |
1 files changed, 17 insertions, 23 deletions
diff --git a/sysdeps/posix/readv.c b/sysdeps/posix/readv.c index f0e78e6662..50bcc91315 100644 --- a/sysdeps/posix/readv.c +++ b/sysdeps/posix/readv.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1991, 1992, 1996, 1997, 2002 Free Software Foundation, Inc. +/* Copyright (C) 1991,1992,1996,1997,2002,2009 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -25,24 +25,24 @@ #include <sys/uio.h> #include <errno.h> + +static void +ifree (char **ptrp) +{ + free (*ptrp); +} + /* Read data from file descriptor FD, and put the result in the - buffers described by VECTOR, which is a vector of COUNT `struct iovec's. + buffers described by VECTOR, which is a vector of COUNT 'struct iovec's. The buffers are filled in the order specified. - Operates just like `read' (see <unistd.h>) except that data are + Operates just like 'read' (see <unistd.h>) except that data are put in VECTOR instead of a contiguous buffer. */ ssize_t __libc_readv (int fd, const struct iovec *vector, int count) { - char *buffer; - char *buffer_start; - size_t bytes; - ssize_t bytes_read; - int i; - bool use_malloc = false; - /* Find the total number of bytes to be read. */ - bytes = 0; - for (i = 0; i < count; ++i) + size_t bytes = 0; + for (int i = 0; i < count; ++i) { /* Check for ssize_t overflow. */ if (SSIZE_MAX - bytes < vector[i].iov_len) @@ -57,28 +57,25 @@ __libc_readv (int fd, const struct iovec *vector, int count) use alloca since it's faster and does not require synchronization with other threads. But we cannot if the amount of memory required is too large. */ + char *buffer; + char *malloced_buffer __attribute__ ((__cleanup__ (ifree))) = NULL; if (__libc_use_alloca (bytes)) buffer = (char *) __alloca (bytes); else { - buffer = (char *) malloc (bytes); + malloced_buffer = buffer = (char *) malloc (bytes); if (buffer == NULL) - /* XXX I don't know whether it is acceptable to try reading - the data in chunks. Probably not so we just fail here. */ return -1; - - use_malloc = true; } /* Read the data. */ - bytes_read = __read (fd, buffer, bytes); + ssize_t bytes_read = __read (fd, buffer, bytes); if (bytes_read <= 0) return -1; /* Copy the data from BUFFER into the memory specified by VECTOR. */ bytes = bytes_read; - buffer_start = buffer; - for (i = 0; i < count; ++i) + for (int i = 0; i < count; ++i) { size_t copy = MIN (vector[i].iov_len, bytes); @@ -90,9 +87,6 @@ __libc_readv (int fd, const struct iovec *vector, int count) break; } - if (use_malloc) - free (buffer_start); - return bytes_read; } #ifndef __libc_readv |