string like operation

CHANGELOG.md

@@ -24,10 +24,13 @@
   ([#392][392]).
 * i3/sway: `output` tag, reflecting the output (monitor) a workspace
   is on.
+* Added "string like" `~~` operator to Map particle. Allows
+  glob-style matching on strings using `*` and `?` characters. ([#400][400])
 
 [96]: https://codeberg.org/dnkl/yambar/issues/96
 [380]: https://codeberg.org/dnkl/yambar/issues/380
 [392]: https://codeberg.org/dnkl/yambar/issues/392
+[400]: https://codeberg.org/dnkl/yambar/pulls/400
 
 
 ### Changed

doc/yambar-particles.5.scd

@@ -265,6 +265,26 @@ To match for empty strings, use ' "" ':
 <tag> == ""
 ```
 
+String glob matching
+
+To perform string matching using globbing with "\*" & "?" characters:
+\* Match any zero or more characters.
+? Match exactly any one character.
+
+```
+<tag> ~~ "hello*"
+```
+
+Will match any string starting with "hello", including "hello", 
+"hello1", "hello123", etc.
+
+```
+<tag> ~~ "hello?"
+```
+
+Will match any string starting with "hello" followed by any single 
+character, including "hello1", "hello-", but not "hello".
+
 Furthermore, you may use the boolean operators:
 
 [-  &&

particles/map.c

@@ -13,6 +13,59 @@
 
 #include "map.h"
 
+// String globbing match.
+// Note: Uses "non-greedy" implementation for "*" wildcard matching
+static bool
+string_like(const char* name, const char* pattern)
+{
+    LOG_DBG("pattern:%s name:%s", pattern, name);
+    int px = 0, nx = 0;
+    int nextpx = 0, nextnx = 0;
+    while(px < strlen(pattern) || nx < strlen(name))
+    {
+        if(px < strlen(pattern))
+        {
+            char c = pattern[px];
+            switch (c) {
+            case '?': {
+                // single character
+                px++;
+                nx++;
+                continue;
+            }
+            case '*': {
+                // zero or more glob
+                nextpx=px;
+                nextnx=nx+1;
+                px++;
+                continue;
+            }
+            default: {
+                // normal character
+                if (nx < strlen(name) && name[nx] == c)
+                {
+                    px++;
+                    nx++;
+                    continue;
+                }
+            }
+            }
+
+        }
+        // mismatch
+		if (0 < nextnx && nextnx <= strlen(name)) {
+			px = nextpx;
+			nx = nextnx;
+			continue;
+		}
+        return false;
+
+    }
+    LOG_DBG("map: name %s matched all the pattern %s", name, pattern);
+    // Matched all of pattern to all of name. Success.
+	return true;
+}
+
 static bool
 int_condition(const long tag_value, const long cond_value, enum map_op op)
 {
@@ -75,6 +128,8 @@ str_condition(const char *tag_value, const char *cond_value, enum map_op op)
         return strcmp(tag_value, cond_value) >= 0;
     case MAP_OP_GT:
         return strcmp(tag_value, cond_value) > 0;
+    case MAP_OP_LIKE:
+        return string_like(tag_value, cond_value) != 0;
     case MAP_OP_SELF:
         LOG_WARN("using String tag as bool");
     default:
@@ -166,6 +221,7 @@ free_map_condition(struct map_condition *c)
     case MAP_OP_LE:
     case MAP_OP_LT:
     case MAP_OP_GE:
+    case MAP_OP_LIKE:
     case MAP_OP_GT:
         free(c->value);
         /* FALLTHROUGH */

particles/map.h

@@ -9,6 +9,7 @@ enum map_op {
     MAP_OP_GT,
     MAP_OP_SELF,
     MAP_OP_NOT,
+    MAP_OP_LIKE,
 
     MAP_OP_AND,
     MAP_OP_OR,

particles/map.l

@@ -69,6 +69,7 @@ void yyerror(const char *s);
 \<                      yylval.op = MAP_OP_LT; return CMP_OP;
 >=                      yylval.op = MAP_OP_GE; return CMP_OP;
 >                       yylval.op = MAP_OP_GT; return CMP_OP;
+~~                      yylval.op = MAP_OP_LIKE; return CMP_OP;
 &&                      yylval.op = MAP_OP_AND; return BOOL_OP;
 \|\|                    yylval.op = MAP_OP_OR; return BOOL_OP;
 ~                       return NOT;

particles/map.y

@@ -79,7 +79,7 @@ static char const*
 token_to_str(yysymbol_kind_t tkn)
 {
     switch (tkn) {
-    case YYSYMBOL_CMP_OP: return "==, !=, <=, <, >=, >";
+    case YYSYMBOL_CMP_OP: return "==, !=, <=, <, >=, >, ~~";
     case YYSYMBOL_BOOL_OP: return "||, &&";
     case YYSYMBOL_L_PAR: return "(";
     case YYSYMBOL_R_PAR: return ")";