[Qemu-devel] [PATCH v8 2/6] sockets: Make port specification optional in inet_parse

[Bharata B Rao <bharata@linux.vnet.ibm.com>]

sockets: Make port specification optional in inet_parse

From: Bharata B Rao <bharata@linux.vnet.ibm.com>

Change inet_parse() to work without explicit port specification. Add a
default_port argument to be used when port isn't specified.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
---

 qemu-sockets.c |   43 ++++++++++++++++++++++++++++++++++---------
 1 files changed, 34 insertions(+), 9 deletions(-)


diff --git a/qemu-sockets.c b/qemu-sockets.c
index b292311..25285f2 100644
--- a/qemu-sockets.c
+++ b/qemu-sockets.c
@@ -406,26 +406,36 @@ err:
     return -1;
 }
 
-/* compatibility wrapper */
-static int inet_parse(QemuOpts *opts, const char *str)
+/*
+ * Converts inet address and port specification in @str to QemuOpts
+ * options.
+ *
+ * If port isn't specified in @str, @default_port will be set in the
+ * port option of @opts. If default_port is -1, then the parser will
+ * look for the port specification in @str mandatorily.
+ */
+static int inet_parse(QemuOpts *opts, const char *str, int default_port)
 {
     const char *optstr, *h;
     char addr[64];
     char port[33];
-    int pos;
+    int ret, pos, addr_pos = -1, port_pos = -1;
 
     /* parse address */
     if (str[0] == ':') {
         /* no host given */
         addr[0] = '\0';
-        if (1 != sscanf(str,":%32[^,]%n",port,&pos)) {
+        ret = sscanf(str, ":%32[^,]%n", port, &port_pos);
+        if (port_pos == -1 || ret == EOF) {
             fprintf(stderr, "%s: portonly parse error (%s)\n",
                     __FUNCTION__, str);
             return -1;
         }
     } else if (str[0] == '[') {
         /* IPv6 addr */
-        if (2 != sscanf(str,"[%64[^]]]:%32[^,]%n",addr,port,&pos)) {
+        ret = sscanf(str, "[%64[^]]]%n:%32[^,]%n", addr, &addr_pos,
+            port, &port_pos);
+        if (addr_pos == -1 || ret == EOF) {
             fprintf(stderr, "%s: ipv6 parse error (%s)\n",
                     __FUNCTION__, str);
             return -1;
@@ -433,7 +443,9 @@ static int inet_parse(QemuOpts *opts, const char *str)
         qemu_opt_set(opts, "ipv6", "on");
     } else if (qemu_isdigit(str[0])) {
         /* IPv4 addr */
-        if (2 != sscanf(str,"%64[0-9.]:%32[^,]%n",addr,port,&pos)) {
+        ret = sscanf(str, "%64[0-9.]%n:%32[^,]%n", addr, &addr_pos,
+            port, &port_pos);
+        if (addr_pos == -1 || ret == EOF) {
             fprintf(stderr, "%s: ipv4 parse error (%s)\n",
                     __FUNCTION__, str);
             return -1;
@@ -441,12 +453,25 @@ static int inet_parse(QemuOpts *opts, const char *str)
         qemu_opt_set(opts, "ipv4", "on");
     } else {
         /* hostname */
-        if (2 != sscanf(str,"%64[^:]:%32[^,]%n",addr,port,&pos)) {
+        ret = sscanf(str, "%64[^:]%n:%32[^,]%n", addr, &addr_pos,
+            port, &port_pos);
+        if (addr_pos == -1 || ret == EOF) {
             fprintf(stderr, "%s: hostname parse error (%s)\n",
                     __FUNCTION__, str);
             return -1;
         }
     }
+
+    if (port_pos != -1) {
+        pos = port_pos;
+    } else {
+        pos = addr_pos;
+        if (default_port == -1) {
+            return -1;
+        }
+        snprintf(port, 33, "%d", default_port);
+    }
+
     qemu_opt_set(opts, "host", addr);
     qemu_opt_set(opts, "port", port);
 
@@ -470,7 +495,7 @@ int inet_listen(const char *str, char *ostr, int olen,
     int sock = -1;
 
     opts = qemu_opts_create(&socket_opts, NULL, 0, NULL);
-    if (inet_parse(opts, str) == 0) {
+    if (inet_parse(opts, str, -1) == 0) {
         sock = inet_listen_opts(opts, port_offset, errp);
         if (sock != -1 && ostr) {
             optstr = strchr(str, ',');
@@ -499,7 +524,7 @@ int inet_connect(const char *str, bool block, bool *in_progress, Error **errp)
     int sock = -1;
 
     opts = qemu_opts_create(&socket_opts, NULL, 0, NULL);
-    if (inet_parse(opts, str) == 0) {
+    if (inet_parse(opts, str, -1) == 0) {
         if (block) {
             qemu_opt_set(opts, "block", "on");
         }