[Qemu-devel] [PATCH 2/7] qemu-img convert: Detect options specified more than once

[Kevin Wolf <kwolf@redhat.com>]

Instead of ignoring all option values but the last one, error out if an
option is set multiple times.

Again, the only exception is a -o help option, which may be added to any
valid qemu-img convert command and ignores all other options.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
 qemu-img.c | 49 +++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 45 insertions(+), 4 deletions(-)

diff --git a/qemu-img.c b/qemu-img.c
index 6a64fe1..55c2c75 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1170,6 +1170,7 @@ static int img_convert(int argc, char **argv)
     QEMUOptionParameter *param = NULL, *create_options = NULL;
     QEMUOptionParameter *out_baseimg_param;
     char *options = NULL;
+    bool options_help = false;
     const char *snapshot_name = NULL;
     int min_sparse = 8; /* Need at least 4k of zeros for sparse detection */
     bool quiet = false;
@@ -1177,8 +1178,8 @@ static int img_convert(int argc, char **argv)
     QemuOpts *sn_opts = NULL;
 
     fmt = NULL;
-    out_fmt = "raw";
-    cache = "unsafe";
+    out_fmt = NULL;
+    cache = NULL;
     out_baseimg = NULL;
     compress = 0;
     skip_create = 0;
@@ -1193,12 +1194,24 @@ static int img_convert(int argc, char **argv)
             help();
             break;
         case 'f':
+            if (fmt) {
+                error_report("-f may only be specified once");
+                return 1;
+            }
             fmt = optarg;
             break;
         case 'O':
+            if (out_fmt) {
+                error_report("-O may only be specified once");
+                return 1;
+            }
             out_fmt = optarg;
             break;
         case 'B':
+            if (out_baseimg) {
+                error_report("-B may only be specified once");
+                return 1;
+            }
             out_baseimg = optarg;
             break;
         case 'c':
@@ -1213,12 +1226,29 @@ static int img_convert(int argc, char **argv)
                   "compat6\' instead!");
             return 1;
         case 'o':
-            options = optarg;
+            if (is_help_option(optarg)) {
+                options_help = true;
+            } else if (!options) {
+                options = optarg;
+            } else {
+                error_report("-o cannot be used multiple times. Please use a "
+                             "single -o option with comma-separated settings "
+                             "instead.");
+                return 1;
+            }
             break;
         case 's':
+            if (sn_opts || snapshot_name) {
+                error_report("-l/-s may only be specified once");
+                return 1;
+            }
             snapshot_name = optarg;
             break;
         case 'l':
+            if (sn_opts || snapshot_name) {
+                error_report("-l/-s may only be specified once");
+                return 1;
+            }
             if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) {
                 sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0);
                 if (!sn_opts) {
@@ -1247,6 +1277,10 @@ static int img_convert(int argc, char **argv)
             progress = 1;
             break;
         case 't':
+            if (cache) {
+                error_report("-t may only be specified once");
+                return 1;
+            }
             cache = optarg;
             break;
         case 'q':
@@ -1258,6 +1292,13 @@ static int img_convert(int argc, char **argv)
         }
     }
 
+    if (!out_fmt) {
+        out_fmt = "raw";
+    }
+    if (!cache) {
+        cache = "unsafe";
+    }
+
     if (quiet) {
         progress = 0;
     }
@@ -1272,7 +1313,7 @@ static int img_convert(int argc, char **argv)
     /* Initialize before goto out */
     qemu_progress_init(progress, 1.0);
 
-    if (options && is_help_option(options)) {
+    if (options_help) {
         ret = print_block_option_help(out_filename, out_fmt);
         goto out;
     }
-- 
1.8.1.4