[Qemu-devel] [PATCH 07/19] Never overwrite a QemuOpt

[Mark McLoughlin <markmc@redhat.com>]

Rather than overwriting a QemuOpt, just add a new one to the tail and
always do a reverse search for parameters to preserve the same
behaviour. We use this order so that foreach() iterates over the opts
in their original order.

This will allow us handle options where multiple values for the same
parameter is allowed - e.g. -net user,hostfwd=

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
---
 qemu-option.c |   51 +++++++++++++++++++++++----------------------------
 1 files changed, 23 insertions(+), 28 deletions(-)

diff --git a/qemu-option.c b/qemu-option.c
index 0f517d1..376efc1 100644
--- a/qemu-option.c
+++ b/qemu-option.c
@@ -483,7 +483,7 @@ struct QemuOpt {
 struct QemuOpts {
     const char *id;
     QemuOptsList *list;
-    TAILQ_HEAD(, QemuOpt) head;
+    TAILQ_HEAD(QemuOptHead, QemuOpt) head;
     TAILQ_ENTRY(QemuOpts) next;
 };
 
@@ -491,7 +491,7 @@ static QemuOpt *qemu_opt_find(QemuOpts *opts, const char *name)
 {
     QemuOpt *opt;
 
-    TAILQ_FOREACH(opt, &opts->head, next) {
+    TAILQ_FOREACH_REVERSE(opt, &opts->head, QemuOptHead, next) {
         if (strcmp(opt->name, name) != 0)
             continue;
         return opt;
@@ -565,36 +565,31 @@ static void qemu_opt_del(QemuOpt *opt)
 int qemu_opt_set(QemuOpts *opts, const char *name, const char *value)
 {
     QemuOpt *opt;
+    QemuOptDesc *desc = opts->list->desc;
+    int i;
 
-    opt = qemu_opt_find(opts, name);
-    if (!opt) {
-        QemuOptDesc *desc = opts->list->desc;
-        int i;
-
-        for (i = 0; desc[i].name != NULL; i++) {
-            if (strcmp(desc[i].name, name) == 0) {
-                break;
-            }
-        }
-        if (desc[i].name == NULL) {
-            if (i == 0) {
-                /* empty list -> allow any */;
-            } else {
-                fprintf(stderr, "option \"%s\" is not valid for %s\n",
-                        name, opts->list->name);
-                return -1;
-            }
+    for (i = 0; desc[i].name != NULL; i++) {
+        if (strcmp(desc[i].name, name) == 0) {
+            break;
         }
-        opt = qemu_mallocz(sizeof(*opt));
-        opt->name = qemu_strdup(name);
-        opt->opts = opts;
-        TAILQ_INSERT_TAIL(&opts->head, opt, next);
-        if (desc[i].name != NULL) {
-            opt->desc = desc+i;
+    }
+    if (desc[i].name == NULL) {
+        if (i == 0) {
+            /* empty list -> allow any */;
+        } else {
+            fprintf(stderr, "option \"%s\" is not valid for %s\n",
+                    name, opts->list->name);
+            return -1;
         }
     }
-    qemu_free((/* !const */ char*)opt->str);
-    opt->str = NULL;
+
+    opt = qemu_mallocz(sizeof(*opt));
+    opt->name = qemu_strdup(name);
+    opt->opts = opts;
+    TAILQ_INSERT_TAIL(&opts->head, opt, next);
+    if (desc[i].name != NULL) {
+        opt->desc = desc+i;
+    }
     if (value) {
         opt->str = qemu_strdup(value);
     }
-- 
1.6.2.5