Am 22.04.2013 20:53, schrieb Paolo Bonzini:
> Commit e9d8fbf (qemu-file: do not use stdio for qemu_fdopen, 2013-03-27)
> introduced a usage of writev, which mingw32 does not have. Even though
> qemu_fdopen itself is not used on mingw32, the future-proof solution is
> to add an implementation of it. This is simple and similar to how we
> emulate sendmsg/recvmsg in util/iov.c.
>
> Some files include osdep.h without qemu-common.h, so move the definition
> of iovec to osdep.h too, and include osdep.h from qemu-common.h
> unconditionally (protection against including files when NEED_CPU_H is
> defined is not needed since the removal of AREG0).
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> include/qemu-common.h | 22 ++--------------------
> include/qemu/osdep.h | 16 ++++++++++++++++
> util/iov.c | 2 +-
> util/osdep.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 61 insertions(+), 21 deletions(-)
>
> diff --git a/include/qemu-common.h b/include/qemu-common.h
> index 3b1873e..2cfb1f0 100644
> --- a/include/qemu-common.h
> +++ b/include/qemu-common.h
> @@ -84,20 +84,6 @@
> # error Unknown pointer size
> #endif
>
> -#ifndef CONFIG_IOVEC
> -#define CONFIG_IOVEC
> -struct iovec {
> - void *iov_base;
> - size_t iov_len;
> -};
> -/*
> - * Use the same value as Linux for now.
> - */
> -#define IOV_MAX 1024
> -#else
> -#include <sys/uio.h>
> -#endif
> -
> typedef int (*fprintf_function)(FILE *f, const char *fmt, ...)
> GCC_FMT_ATTR(2, 3);
>
> @@ -122,16 +108,12 @@ static inline char *realpath(const char *path, char
> *resolved_path)
> void configure_icount(const char *option);
> extern int use_icount;
>
> -/* FIXME: Remove NEED_CPU_H. */
> -#ifndef NEED_CPU_H
> -
> #include "qemu/osdep.h"
> #include "qemu/bswap.h"
>
> -#else
> -
> +/* FIXME: Remove NEED_CPU_H. */
> +#ifdef NEED_CPU_H
> #include "cpu.h"
> -
> #endif /* !defined(NEED_CPU_H) */
>
> /* main function, renamed */
> diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
> index 8b465fd..e2697d6 100644
> --- a/include/qemu/osdep.h
> +++ b/include/qemu/osdep.h
> @@ -161,6 +161,22 @@ int qemu_close(int fd);
> int qemu_create_pidfile(const char *filename);
> int qemu_get_thread_id(void);
>
> +#ifndef CONFIG_IOVEC
> +struct iovec {
> + void *iov_base;
> + size_t iov_len;
> +};
> +/*
> + * Use the same value as Linux for now.
> + */
> +#define IOV_MAX 1024
> +
> +ssize_t readv(int fd, struct iovec *iov, unsigned iov_cnt);
> +ssize_t writev(int fd, struct iovec *iov, unsigned iov_cnt);
> +#else
> +#include <sys/uio.h>
> +#endif
> +
> #ifdef _WIN32
> static inline void qemu_timersub(const struct timeval *val1,
> const struct timeval *val2,
> diff --git a/util/iov.c b/util/iov.c
> index d32226d..78bbbe1 100644
> --- a/util/iov.c
> +++ b/util/iov.c
> @@ -99,7 +99,7 @@ size_t iov_size(const struct iovec *iov, const unsigned int
> iov_cnt)
> static ssize_t
> do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
> {
> -#if defined CONFIG_IOVEC && defined CONFIG_POSIX
> +#ifdef CONFIG_POSIX
> ssize_t ret;
> struct msghdr msg;
> memset(&msg, 0, sizeof(msg));
> diff --git a/util/osdep.c b/util/osdep.c
> index bd59ac9..5f306a6 100644
> --- a/util/osdep.c
> +++ b/util/osdep.c
> @@ -406,3 +406,45 @@ bool fips_get_state(void)
> return fips_enabled;
> }
>
> +#ifndef CONFIG_IOVEC
> +/* helper function for iov_send_recv() */
> +static ssize_t
> +readv_writev(int fd, struct iovec *iov, unsigned iov_cnt, bool do_write)
> +{
> + unsigned i = 0;
> + ssize_t ret = 0;
> + while (i < iov_cnt) {
> + ssize_t r = do_write
> + ? write(fd, iov[i].iov_base, iov[i].iov_len)
> + : read(fd, iov[i].iov_base, iov[i].iov_len);
> + if (r > 0) {
> + ret += r;
> + } else if (!r) {
> + break;
> + } else if (errno == EINTR) {
> + continue;
> + } else {
> + /* else it is some "other" error,
> + * only return if there was no data processed. */
> + if (ret == 0) {
> + ret = -1;
> + }
> + break;
> + }
> + i++;
> + }
> + return ret;
> +}
> +
> +ssize_t
> +readv(int fd, struct iovec *iov, unsigned iov_cnt)
> +{
> + return readv_writev(fd, iov, iov_cnt, false);
> +}
> +
> +ssize_t
> +writev(int fd, struct iovec *iov, unsigned iov_cnt)
> +{
> + return readv_writev(fd, iov, iov_cnt, true);
> +}
> +#endif
Hi Paolo,
your patch looks good, but maybe you could modify the signatures
of readv, writev to match the Linux originals (missing const, use int):
ssize_t readv(int fd, const struct iovec *iov, int iovcnt);
ssize_t writev(int fd, const struct iovec *iov, int iovcnt);
In an updated patch the tab characters could be replaced by a space
to make checkpatch.pl happy.
Regards,
Stefan
