Re: [Qemu-devel] [PATCH] multiboot: Support quotable commas in module list

[Adam Lackorzynski <adam@os.inf.tu-dresden.de>]

On Fri Apr 15, 2011 at 15:17:28 +0200, Kevin Wolf wrote:
> Am 15.04.2011 09:56, schrieb Adam Lackorzynski:
> > Support quoting of ',' (and '\') to allow commas in the parameter list of
> > modules.
> > 
> > Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
> 
> Other options in qemu use double commas for escaping. So maybe reusing
> get_opt_value() would make things more consistent. It also has the
> advantage that double commas don't need additional escape characters for
> the shell.
> 
> On the other hand, using backslashes for escaping is probably more
> familiar for most people, so I don't have a very strong opinion on it.

Same for me. I like the fact with the double-commas and easier shell
quoting. On the other side using backslashes is more common. However, I
construct the overall command via scripts anyway, so I'll only very
seldom actually type this myself.

Here's how it would look like. Diff is smaller.
More opinions very welcome.


diff --git a/hw/multiboot.c b/hw/multiboot.c
index 394ed01..7d5cb22 100644
--- a/hw/multiboot.c
+++ b/hw/multiboot.c
@@ -97,11 +97,11 @@ typedef struct {
 
 static uint32_t mb_add_cmdline(MultibootState *s, const char *cmdline)
 {
-    int len = strlen(cmdline) + 1;
     target_phys_addr_t p = s->offset_cmdlines;
+    char *b = (char *)s->mb_buf + p;
 
-    pstrcpy((char *)s->mb_buf + p, len, cmdline);
-    s->offset_cmdlines += len;
+    get_opt_value(b, strlen(cmdline) + 1, cmdline);
+    s->offset_cmdlines += strlen(b) + 1;
     return s->mb_buf_phys + p;
 }
 
@@ -238,7 +238,7 @@ int load_multiboot(void *fw_cfg,
         const char *r = initrd_filename;
         mbs.mb_buf_size += strlen(r) + 1;
         mbs.mb_mods_avail = 1;
-        while ((r = strchr(r, ','))) {
+        while (*(r = get_opt_value(NULL, 0, r))) {
            mbs.mb_mods_avail++;
            r++;
         }
@@ -252,7 +252,7 @@ int load_multiboot(void *fw_cfg,
     mbs.offset_cmdlines = mbs.offset_mbinfo + mbs.mb_mods_avail * MB_MOD_SIZE;
 
     if (initrd_filename) {
-        char *next_initrd;
+        char *next_initrd, not_last;
 
         mbs.offset_mods = mbs.mb_buf_size;
 
@@ -261,9 +261,9 @@ int load_multiboot(void *fw_cfg,
             int mb_mod_length;
             uint32_t offs = mbs.mb_buf_size;
 
-            next_initrd = strchr(initrd_filename, ',');
-            if (next_initrd)
-                *next_initrd = '\0';
+            next_initrd = (char *)get_opt_value(NULL, 0, initrd_filename);
+            not_last = *next_initrd;
+            *next_initrd = '\0';
             /* if a space comes after the module filename, treat everything
                after that as parameters */
             target_phys_addr_t c = mb_add_cmdline(&mbs, initrd_filename);
@@ -287,7 +287,7 @@ int load_multiboot(void *fw_cfg,
                      (char *)mbs.mb_buf + offs,
                      (char *)mbs.mb_buf + offs + mb_mod_length, c);
             initrd_filename = next_initrd+1;
-        } while (next_initrd);
+        } while (not_last);
     }
 
     /* Commandline support */



Adam
-- 
Adam                 adam@os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/