qemu: support disk filenames with comma

If there is a disk file with a comma in the name, QEmu expects a double
comma instead of a single one (e.g., the file "virtual,disk.img" needs
to be specified as "virtual,,disk.img" in QEmu's command line). This
patch fixes libvirt to work with that feature. Fix RHBZ #801036.

Based on an initial patch by Crístian Viana.

* src/util/buf.h (virBufferEscape): Alter signature.
* src/util/buf.c (virBufferEscape): Add parameter.
(virBufferEscapeSexpr): Fix caller.
* src/qemu/qemu_command.c (qemuBuildRBDString): Likewise.  Also
escape commas in file names.
(qemuBuildDriveStr): Escape commas in file names.
* docs/schemas/basictypes.rng (absFilePath): Relax RNG to allow
commas in input file names.
* tests/qemuxml2argvdata/*-disk-drive-network-sheepdog.*: Update
test.

Signed-off-by: Eric Blake <eblake@redhat.com>

src/qemu/qemu_command.c

@@ -1629,6 +1629,7 @@ qemuSafeSerialParamValue(const char *value)
     return 0;
 }
 
+
 static int
 qemuBuildRBDString(virConnectPtr conn,
                    virDomainDiskDefPtr disk,
@@ -1639,9 +1640,9 @@ qemuBuildRBDString(virConnectPtr conn,
     char *secret = NULL;
     size_t secret_size;
 
-    virBufferAsprintf(opt, "rbd:%s", disk->src);
+    virBufferEscape(opt, ',', ",", "rbd:%s", disk->src);
     if (disk->auth.username) {
-        virBufferEscape(opt, ":", ":id=%s", disk->auth.username);
+        virBufferEscape(opt, '\\', ":", ":id=%s", disk->auth.username);
         /* look up secret */
         switch (disk->auth.secretType) {
         case VIR_DOMAIN_DISK_SECRET_TYPE_UUID:
@@ -1672,7 +1673,8 @@ qemuBuildRBDString(virConnectPtr conn,
                 virReportOOMError();
                 goto error;
             }
-            virBufferEscape(opt, ":", ":key=%s:auth_supported=cephx none",
+            virBufferEscape(opt, '\\', ":",
+                            ":key=%s:auth_supported=cephx none",
                             base64);
             VIR_FREE(base64);
         } else {
@@ -1923,9 +1925,10 @@ qemuBuildDriveStr(virConnectPtr conn ATTRIBUTE_UNUSED,
                 goto error;
             }
             if (disk->device == VIR_DOMAIN_DISK_DEVICE_FLOPPY)
-                virBufferAsprintf(&opt, "file=fat:floppy:%s,", disk->src);
+                virBufferEscape(&opt, ',', ",", "file=fat:floppy:%s,",
+                                disk->src);
             else
-                virBufferAsprintf(&opt, "file=fat:%s,", disk->src);
+                virBufferEscape(&opt, ',', ",", "file=fat:%s,", disk->src);
         } else if (disk->type == VIR_DOMAIN_DISK_TYPE_NETWORK) {
             switch (disk->protocol) {
             case VIR_DOMAIN_DISK_PROTOCOL_NBD:
@@ -1944,17 +1947,19 @@ qemuBuildDriveStr(virConnectPtr conn ATTRIBUTE_UNUSED,
                 virBufferAddChar(&opt, ',');
                 break;
             case VIR_DOMAIN_DISK_PROTOCOL_SHEEPDOG:
-                if (disk->nhosts == 0)
-                    virBufferAsprintf(&opt, "file=sheepdog:%s,", disk->src);
-                else
+                if (disk->nhosts == 0) {
+                    virBufferEscape(&opt, ',', ",", "file=sheepdog:%s,",
+                                    disk->src);
+                } else {
                     /* only one host is supported now */
-                    virBufferAsprintf(&opt, "file=sheepdog:%s:%s:%s,",
-                                      disk->hosts->name, disk->hosts->port,
-                                      disk->src);
+                    virBufferAsprintf(&opt, "file=sheepdog:%s:%s:",
+                                      disk->hosts->name, disk->hosts->port);
+                    virBufferEscape(&opt, ',', ",", "%s,", disk->src);
+                }
                 break;
             }
         } else {
-            virBufferAsprintf(&opt, "file=%s,", disk->src);
+            virBufferEscape(&opt, ',', ",", "file=%s,", disk->src);
         }
     }
     if (qemuCapsGet(qemuCaps, QEMU_CAPS_DEVICE))
@@ -2135,7 +2140,6 @@ error:
     return NULL;
 }
 
-
 char *
 qemuBuildDriveDevStr(virDomainDefPtr def,
                      virDomainDiskDefPtr disk,
@@ -6130,7 +6134,14 @@ qemuParseKeywords(const char *str,
         char *keyword;
         char *value = NULL;
 
-        if (!(endmark = strchr(start, ',')))
+        endmark = start;
+        do {
+            /* Qemu accepts ',,' as an escape for a literal comma;
+             * skip past those here while searching for the end of the
+             * value, then strip them down below */
+            endmark = strchr(endmark, ',');
+        } while (endmark && endmark[1] == ',' && (endmark += 2));
+        if (!endmark)
             endmark = end;
         if (!(separator = strchr(start, '=')))
             separator = end;
@@ -6153,6 +6164,16 @@ qemuParseKeywords(const char *str,
                 VIR_FREE(keyword);
                 goto no_memory;
             }
+            if (strchr(value, ',')) {
+                char *p = strchr(value, ',') + 1;
+                char *q = p + 1;
+                while (*q) {
+                    if (*q == ',')
+                        q++;
+                    *p++ = *q++;
+                }
+                *p = '\0';
+            }
         }
 
         if (keywordAlloc == keywordCount) {

src/util/buf.c

@@ -1,7 +1,7 @@
 /*
  * buf.c: buffers for libvirt
  *
- * Copyright (C) 2005-2008, 2010-2011 Red Hat, Inc.
+ * Copyright (C) 2005-2008, 2010-2012 Red Hat, Inc.
  *
  * See COPYING.LIB for the License of this software
  *
@@ -423,22 +423,23 @@ virBufferEscapeSexpr(virBufferPtr buf,
                      const char *format,
                      const char *str)
 {
-    virBufferEscape(buf, "\\'", format, str);
+    virBufferEscape(buf, '\\', "\\'", format, str);
 }
 
 /**
  * virBufferEscape:
  * @buf: the buffer to append to
+ * @escape: the escape character to inject
  * @toescape: NUL-terminated list of characters to escape
  * @format: a printf like format string but with only one %s parameter
  * @str: the string argument which needs to be escaped
  *
  * Do a formatted print with a single string to a buffer.  Any characters
- * in the provided list are escaped with a preceeding \.  Auto indentation
+ * in the provided list are escaped with the given escape.  Auto indentation
  * may be applied.
  */
 void
-virBufferEscape(virBufferPtr buf, const char *toescape,
+virBufferEscape(virBufferPtr buf, char escape, const char *toescape,
                 const char *format, const char *str)
 {
     int len;
@@ -471,7 +472,7 @@ virBufferEscape(virBufferPtr buf, const char *toescape,
          */
         char needle[2] = { *cur, 0 };
         if (strstr(toescape, needle))
-            *out++ = '\\';
+            *out++ = escape;
         *out++ = *cur;
         cur++;
     }

src/util/buf.h

@@ -1,7 +1,7 @@
 /*
  * buf.h: buffers for libvirt
  *
- * Copyright (C) 2005-2008, 2011 Red Hat, Inc.
+ * Copyright (C) 2005-2008, 2011, 2012 Red Hat, Inc.
  *
  * See COPYING.LIB for the License of this software
  *
@@ -49,7 +49,7 @@ void virBufferVasprintf(virBufferPtr buf, const char *format, va_list ap)
   ATTRIBUTE_FMT_PRINTF(2, 0);
 void virBufferStrcat(virBufferPtr buf, ...)
   ATTRIBUTE_SENTINEL;
-void virBufferEscape(virBufferPtr buf, const char *toescape,
+void virBufferEscape(virBufferPtr buf, char escape, const char *toescape,
                      const char *format, const char *str);
 void virBufferEscapeString(virBufferPtr buf, const char *format,
                            const char *str);