[PATCH] support colon in filenames

[Ram Pai <linuxram@us.ibm.com>]

Problem: It is impossible to feed filenames with the character colon because 
qemu interprets such names as a protocol. For example  a filename scsi:0,
is interpreted as a protocol by name "scsi".

This patch allows users to espace colon characters. For example the above filename
can now be expressed as 'scsi\:0'

Here are couple of examples:

ndb:\::9999  is treated as a ndb protocol with a hostname ':' on port 9999
scsi\:0\:abc is a local file scsi:0:abc
http\://myweb is a local file by name http://myweb
nbd\::localhost:2558  is a protocol by name nbd: 

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
-----------------------------------------------------------------------


 block.c           |   26 +++++++++++++++++---------
 block/nbd.c       |   19 ++++++++++++++-----
 block/raw-posix.c |   24 +++++++++++++++++-------
 cutils.c          |   22 ++++++++++++++++++++++
 qemu-common.h     |    1 +
 vl.c              |    3 +--
 6 files changed, 72 insertions(+), 23 deletions(-)

diff --git a/block.c b/block.c
index aca5a6d..80bded9 100644
--- a/block.c
+++ b/block.c
@@ -225,22 +225,30 @@ static BlockDriver *find_protocol(const char *filename)
 {
     BlockDriver *drv1;
     char protocol[128];
-    int len;
-    const char *p;
+    char *p = protocol; 
+    const char *f=filename;
+    int len = strnlen(filename, 128);
 
 #ifdef _WIN32
     if (is_windows_drive(filename) ||
         is_windows_drive_prefix(filename))
         return bdrv_find_format("raw");
 #endif
-    p = strchr(filename, ':');
-    if (!p)
+    while ( f < filename+len ) {
+	if ( *f == ':' )
+		break;
+	if ( *f == '\\') {
+		f++;
+		if ( *f == '\0')
+			break;
+	}
+	*p++ = *f++;
+    }
+    *p='\0';
+
+    if (*f != ':')
         return bdrv_find_format("raw");
-    len = p - filename;
-    if (len > sizeof(protocol) - 1)
-        len = sizeof(protocol) - 1;
-    memcpy(protocol, filename, len);
-    protocol[len] = '\0';
+
     for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
         if (drv1->protocol_name &&
             !strcmp(drv1->protocol_name, protocol))
diff --git a/block/nbd.c b/block/nbd.c
index 47d4778..a011cc7 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -64,18 +64,27 @@ static int nbd_open(BlockDriverState *bs, const char* filename, int flags)
 
     } else {
         uint16_t port;
-        char *p, *r;
+        char *q, *p, *r;
         char hostname[128];
 
         pstrcpy(hostname, 128, host);
 
-        p = strchr(hostname, ':');
-        if (p == NULL)
+	q=p=hostname;
+	while ( p < hostname+128 ) {
+		if (*p == ':')
+			break;
+		if ( *p == '\\' )  {
+			p++;
+			if (*p =='\0') 
+				break;
+		}
+		*q++=*p++;
+	}
+        if (*p != ':')
             return -EINVAL;
 
-        *p = '\0';
+	*q='\0';
         p++;
-
         port = strtol(p, &r, 0);
         if (r == p)
             return -EINVAL;
diff --git a/block/raw-posix.c b/block/raw-posix.c
index 41bfa37..98ede17 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -124,6 +124,16 @@ static int fd_open(BlockDriverState *bs);
 static int cdrom_reopen(BlockDriverState *bs);
 #endif
 
+static int _open(const char *filename, int flags, ...)
+{
+	char myfile[PATH_MAX];
+   	va_list ap;
+   	va_start(ap, flags);
+	return  open(esc_string(myfile, PATH_MAX, filename),
+				flags, ap);
+}
+
+
 static int raw_open_common(BlockDriverState *bs, const char *filename,
         int flags)
 {
@@ -151,7 +161,7 @@ static int raw_open_common(BlockDriverState *bs, const char *filename,
         s->open_flags |= O_DSYNC;
 
     s->fd = -1;
-    fd = open(filename, s->open_flags, 0644);
+    fd = _open(filename, s->open_flags, 0644);
     if (fd < 0) {
         ret = -errno;
         if (ret == -EROFS)
@@ -844,7 +854,7 @@ static int raw_create(const char *filename, QEMUOptionParameter *options)
         options++;
     }
 
-    fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
+    fd = _open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
               0644);
     if (fd < 0)
         return -EIO;
@@ -985,7 +995,7 @@ static int hdev_open(BlockDriverState *bs, const char *filename, int flags)
         if ( bsdPath[ 0 ] != '\0' ) {
             strcat(bsdPath,"s0");
             /* some CDs don't have a partition 0 */
-            fd = open(bsdPath, O_RDONLY | O_BINARY | O_LARGEFILE);
+            fd = _open(bsdPath, O_RDONLY | O_BINARY | O_LARGEFILE);
             if (fd < 0) {
                 bsdPath[strlen(bsdPath)-1] = '1';
             } else {
@@ -1037,7 +1047,7 @@ static int fd_open(BlockDriverState *bs)
 #endif
             return -EIO;
         }
-        s->fd = open(bs->filename, s->open_flags & ~O_NONBLOCK);
+        s->fd = _open(bs->filename, s->open_flags & ~O_NONBLOCK);
         if (s->fd < 0) {
             s->fd_error_time = qemu_get_clock(rt_clock);
             s->fd_got_error = 1;
@@ -1133,7 +1143,7 @@ static int hdev_create(const char *filename, QEMUOptionParameter *options)
         options++;
     }
 
-    fd = open(filename, O_WRONLY | O_BINARY);
+    fd = _open(filename, O_WRONLY | O_BINARY);
     if (fd < 0)
         return -EIO;
 
@@ -1239,7 +1249,7 @@ static int floppy_eject(BlockDriverState *bs, int eject_flag)
         close(s->fd);
         s->fd = -1;
     }
-    fd = open(bs->filename, s->open_flags | O_NONBLOCK);
+    fd = _open(bs->filename, s->open_flags | O_NONBLOCK);
     if (fd >= 0) {
         if (ioctl(fd, FDEJECT, 0) < 0)
             perror("FDEJECT");
@@ -1399,7 +1409,7 @@ static int cdrom_reopen(BlockDriverState *bs)
      */
     if (s->fd >= 0)
         close(s->fd);
-    fd = open(bs->filename, s->open_flags, 0644);
+    fd = _open(bs->filename, s->open_flags, 0644);
     if (fd < 0) {
         s->fd = -1;
         return -EIO;
diff --git a/cutils.c b/cutils.c
index 6ea0c49..63c196d 100644
--- a/cutils.c
+++ b/cutils.c
@@ -24,6 +24,28 @@
 #include "qemu-common.h"
 #include "host-utils.h"
 
+/*
+ * prune escape character '\'
+ */
+char *esc_string(char *buf, int buf_size, const char *str)
+{
+        const char *p=str;
+        int len = strlen(str);
+        char *q=buf;
+
+	len = (buf_size < len) ? buf_size: len;
+        while (p < str+len) {
+                if (*p == '\\') {
+                        p++;
+			if (*p == '\0')
+				break;
+		}
+                *q++ = *p++;
+        }
+        *q='\0';
+	return buf;
+}
+
 void pstrcpy(char *buf, int buf_size, const char *str)
 {
     int c;
diff --git a/qemu-common.h b/qemu-common.h
index 2dcb224..1e510dc 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -104,6 +104,7 @@ void qemu_get_timedate(struct tm *tm, int offset);
 int qemu_timedate_diff(struct tm *tm);
 
 /* cutils.c */
+char *esc_string(char *buf, int buf_size, const char *str);
 void pstrcpy(char *buf, int buf_size, const char *str);
 char *pstrcat(char *buf, int buf_size, const char *s);
 int strstart(const char *str, const char *val, const char **ptr);
diff --git a/vl.c b/vl.c
index 7278999..5d7b024 100644
--- a/vl.c
+++ b/vl.c
@@ -2583,8 +2583,7 @@ int drive_init(struct drive_opt *arg, int snapshot, void *opaque)
     else if (cache == 3) /* not specified */
         bdrv_flags |= BDRV_O_CACHE_DEF;
     if (bdrv_open2(bdrv, file, bdrv_flags, drv) < 0) {
-        fprintf(stderr, "qemu: could not open disk image %s\n",
-                        file);
+        fprintf(stderr, "qemu: could not open disk image %s\n", file);
         return -1;
     }
     if (bdrv_key_required(bdrv))