Parse XBM images which use character escapes for hex literals

* src/image.c (xbm_scan): Implement parsing of hex escapes in
character literals.

1 files changed, 42 insertions, 0 deletions

diff --git a/src/image.c b/src/image.c
index 5c1bf8d7be6..d012fcea6a7 100644
--- a/src/image.c
+++ b/src/image.c
@@ -3681,6 +3681,48 @@ xbm_scan (char **s, char *end, char *sval, int *ival)
       *ival = value;
       return overflow ? XBM_TK_OVERFLOW : XBM_TK_NUMBER;
     }
+  /* Character literal.  XBM images typically contain hex escape
+     sequences and not actual characters, so we only try to handle
+     that here.  */
+  else if (c == '\'')
+    {
+      int value = 0, digit;
+      bool overflow = false;
+
+      if (*s == end)
+        return 0;
+
+      c = *(*s)++;
+
+      if (c != '\\' || *s == end)
+        return 0;
+
+      c = *(*s)++;
+
+      if (c == 'x')
+        {
+          while (*s < end)
+            {
+              c = *(*s)++;
+
+              if (c == '\'')
+                {
+                  *ival = value;
+                  return overflow ? XBM_TK_OVERFLOW : XBM_TK_NUMBER;
+                }
+
+              digit = char_hexdigit (c);
+
+              if (digit < 0)
+                return 0;
+
+              overflow |= INT_MULTIPLY_WRAPV (value, 16, &value);
+              value += digit;
+            }
+
+          return 0;
+        }
+    }
   else if (c_isalpha (c) || c == '_')
     {
       *sval++ = c;