support colons in SGR character attributes

Patch by Mikhail Kot <to@myrrc.dev>
With some modifications to behave more like xterm (see note below).

Example:

	printf '\033[48;2;255:0:0mtest\n'

https://invisible-island.net/xterm/ctlseqs/ctlseqs.html

Some notes:

"CSI Pm m  Character Attributes (SGR).
[...]
o   xterm allows either colons (standard) or semicolons
(legacy) to separate the subparameters (but after the
first colon, colons must be used).

1 files changed, 4 insertions, 1 deletions

diff --git a/st.c b/st.c
index b9f66e7..57c6e96 100644
--- a/st.c
+++ b/st.c
@@ -1132,6 +1132,7 @@ csiparse(void)
 {
         char *p = csiescseq.buf, *np;
         long int v;
+        int sep = ';'; /* colon or semi-colon, but not both */
 
         csiescseq.narg = 0;
         if (*p == '?') {
@@ -1149,7 +1150,9 @@ csiparse(void)
                         v = -1;
                 csiescseq.arg[csiescseq.narg++] = v;
                 p = np;
-                if (*p != ';' || csiescseq.narg == ESC_ARG_SIZ)
+                if (sep == ';' && *p == ':')
+                        sep = ':'; /* allow override to colon once */
+                if (*p != sep || csiescseq.narg == ESC_ARG_SIZ)
                         break;
                 p++;
         }