[Qemu-devel] [PATCH] qemu-io: Use getopt() correctly

[Qemu-devel] [PATCH] qemu-io: Use getopt() correctly

[Eric Blake]

POSIX says getopt() returns -1 on completion.  While Linux happens
to define EOF as -1, this definition is not required by POSIX, and
there may be platforms where checking for EOF instead of -1 would
lead to an infinite loop.

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 qemu-io-cmds.c | 16 ++++++++--------
 qemu-io.c      |  2 +-
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 1afcfc0..52dc611 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -646,7 +646,7 @@ static int read_f(BlockBackend *blk, int argc, char **argv)
     int total = 0;
     int pattern = 0, pattern_offset = 0, pattern_count = 0;

-    while ((c = getopt(argc, argv, "bCl:pP:qs:v")) != EOF) {
+    while ((c = getopt(argc, argv, "bCl:pP:qs:v")) != -1) {
         switch (c) {
         case 'b':
             bflag = 1;
@@ -830,7 +830,7 @@ static int readv_f(BlockBackend *blk, int argc, char **argv)
     int pattern = 0;
     int Pflag = 0;

-    while ((c = getopt(argc, argv, "CP:qv")) != EOF) {
+    while ((c = getopt(argc, argv, "CP:qv")) != -1) {
         switch (c) {
         case 'C':
             Cflag = 1;
@@ -961,7 +961,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
     int total = 0;
     int pattern = 0xcd;

-    while ((c = getopt(argc, argv, "bcCpP:qz")) != EOF) {
+    while ((c = getopt(argc, argv, "bcCpP:qz")) != -1) {
         switch (c) {
         case 'b':
             bflag = 1;
@@ -1116,7 +1116,7 @@ static int writev_f(BlockBackend *blk, int argc, char **argv)
     int pattern = 0xcd;
     QEMUIOVector qiov;

-    while ((c = getopt(argc, argv, "CqP:")) != EOF) {
+    while ((c = getopt(argc, argv, "CqP:")) != -1) {
         switch (c) {
         case 'C':
             Cflag = 1;
@@ -1228,7 +1228,7 @@ static int multiwrite_f(BlockBackend *blk, int argc, char **argv)
     int i;
     BlockRequest *reqs;

-    while ((c = getopt(argc, argv, "CqP:")) != EOF) {
+    while ((c = getopt(argc, argv, "CqP:")) != -1) {
         switch (c) {
         case 'C':
             Cflag = 1;
@@ -1463,7 +1463,7 @@ static int aio_read_f(BlockBackend *blk, int argc, char **argv)
     struct aio_ctx *ctx = g_new0(struct aio_ctx, 1);

     ctx->blk = blk;
-    while ((c = getopt(argc, argv, "CP:qv")) != EOF) {
+    while ((c = getopt(argc, argv, "CP:qv")) != -1) {
         switch (c) {
         case 'C':
             ctx->Cflag = 1;
@@ -1562,7 +1562,7 @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv)
     struct aio_ctx *ctx = g_new0(struct aio_ctx, 1);

     ctx->blk = blk;
-    while ((c = getopt(argc, argv, "CqP:")) != EOF) {
+    while ((c = getopt(argc, argv, "CqP:")) != -1) {
         switch (c) {
         case 'C':
             ctx->Cflag = 1;
@@ -1779,7 +1779,7 @@ static int discard_f(BlockBackend *blk, int argc, char **argv)
     int64_t offset;
     int count;

-    while ((c = getopt(argc, argv, "Cq")) != EOF) {
+    while ((c = getopt(argc, argv, "Cq")) != -1) {
         switch (c) {
         case 'C':
             Cflag = 1;
diff --git a/qemu-io.c b/qemu-io.c
index 8e41080..ae5e274 100644
--- a/qemu-io.c
+++ b/qemu-io.c
@@ -120,7 +120,7 @@ static int open_f(BlockBackend *blk, int argc, char **argv)
     QemuOpts *qopts;
     QDict *opts;

-    while ((c = getopt(argc, argv, "snrgo:")) != EOF) {
+    while ((c = getopt(argc, argv, "snrgo:")) != -1) {
         switch (c) {
         case 's':
             flags |= BDRV_O_SNAPSHOT;
-- 
2.1.0

Re: [Qemu-devel] [Qemu-block] [PATCH] qemu-io: Use getopt() correctly

[Alberto Garcia]

On Tue 12 May 2015 05:10:56 PM CEST, Eric Blake <eblake@redhat.com> wrote:

> POSIX says getopt() returns -1 on completion.  While Linux happens
> to define EOF as -1, this definition is not required by POSIX, and
> there may be platforms where checking for EOF instead of -1 would
> lead to an infinite loop.
>
> Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>

Berto

Re: [Qemu-devel] [PATCH] qemu-io: Use getopt() correctly

[Kevin Wolf]

Am 12.05.2015 um 17:10 hat Eric Blake geschrieben:
> POSIX says getopt() returns -1 on completion.  While Linux happens
> to define EOF as -1, this definition is not required by POSIX, and
> there may be platforms where checking for EOF instead of -1 would
> lead to an infinite loop.
> 
> Signed-off-by: Eric Blake <eblake@redhat.com>

Thanks, applied to my block branch.

Kevin