Merge branch 'cb/pcre2-chartables-leakfix' into jch

* cb/pcre2-chartables-leakfix:
  grep: avoid leak of chartables in PCRE2
  grep: make PCRE2 aware of custom allocator
  grep: make PCRE1 aware of custom allocator

Author: gitster

builtin/grep.c

@@ -1147,5 +1147,6 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 		run_pager(&opt, prefix);
 	clear_pathspec(&pathspec);
 	free_grep_patterns(&opt);
+	grep_destroy();
 	return !hit;
 }

grep.c

@@ -16,6 +16,20 @@ static int grep_source_is_binary(struct grep_source *gs,
 
 static struct grep_opt grep_defaults;
 
+#ifdef USE_LIBPCRE2
+static pcre2_general_context *pcre2_global_context;
+
+static void *pcre2_malloc(PCRE2_SIZE size, MAYBE_UNUSED void *memory_data)
+{
+	return malloc(size);
+}
+
+static void pcre2_free(void *pointer, MAYBE_UNUSED void *memory_data)
+{
+	return free(pointer);
+}
+#endif
+
 static const char *color_grep_slots[] = {
 	[GREP_COLOR_CONTEXT]	    = "context",
 	[GREP_COLOR_FILENAME]	    = "filename",
@@ -150,12 +164,28 @@ int grep_config(const char *var, const char *value, void *cb)
  * Initialize one instance of grep_opt and copy the
  * default values from the template we read the configuration
  * information in an earlier call to git_config(grep_config).
+ *
+ * If using PCRE, make sure that the library is configured
+ * to use the same allocator as Git (e.g. nedmalloc on Windows).
+ *
+ * Any allocated memory needs to be released in grep_destroy().
  */
 void grep_init(struct grep_opt *opt, struct repository *repo, const char *prefix)
 {
 	struct grep_opt *def = &grep_defaults;
 	int i;
 
+#if defined(USE_LIBPCRE2)
+	if (!pcre2_global_context)
+		pcre2_global_context = pcre2_general_context_create(
+					pcre2_malloc, pcre2_free, NULL);
+#endif
+
+#ifdef USE_LIBPCRE1
+	pcre_malloc = malloc;
+	pcre_free = free;
+#endif
+
 	memset(opt, 0, sizeof(*opt));
 	opt->repo = repo;
 	opt->prefix = prefix;
@@ -178,6 +208,13 @@ void grep_init(struct grep_opt *opt, struct repository *repo, const char *prefix
 		color_set(opt->colors[i], def->colors[i]);
 }
 
+void grep_destroy(void)
+{
+#ifdef USE_LIBPCRE2
+	pcre2_general_context_free(pcre2_global_context);
+#endif
+}
+
 static void grep_set_pattern_type_option(enum grep_pattern_type pattern_type, struct grep_opt *opt)
 {
 	/*
@@ -461,7 +498,6 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt
 	PCRE2_UCHAR errbuf[256];
 	PCRE2_SIZE erroffset;
 	int options = PCRE2_MULTILINE;
-	const uint8_t *character_tables = NULL;
 	int jitret;
 	int patinforet;
 	size_t jitsizearg;
@@ -470,11 +506,15 @@ static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt
 
 	p->pcre2_compile_context = NULL;
 
+	/* pcre2_global_context is initialized in append_grep_pattern */
 	if (opt->ignore_case) {
 		if (!opt->ignore_locale && has_non_ascii(p->pattern)) {
-			character_tables = pcre2_maketables(NULL);
+			if (!pcre2_global_context)
+				BUG("pcre2_global_context uninitialized");
+			p->pcre2_tables = pcre2_maketables(pcre2_global_context);
 			p->pcre2_compile_context = pcre2_compile_context_create(NULL);
-			pcre2_set_character_tables(p->pcre2_compile_context, character_tables);
+			pcre2_set_character_tables(p->pcre2_compile_context,
+							p->pcre2_tables);
 		}
 		options |= PCRE2_CASELESS;
 	}
@@ -571,6 +611,7 @@ static void free_pcre2_pattern(struct grep_pat *p)
 	pcre2_compile_context_free(p->pcre2_compile_context);
 	pcre2_code_free(p->pcre2_pattern);
 	pcre2_match_data_free(p->pcre2_match_data);
+	free((void *)p->pcre2_tables);
 }
 #else /* !USE_LIBPCRE2 */
 static void compile_pcre2_pattern(struct grep_pat *p, const struct grep_opt *opt)

grep.h

@@ -78,6 +78,7 @@ struct grep_pat {
 	pcre2_code *pcre2_pattern;
 	pcre2_match_data *pcre2_match_data;
 	pcre2_compile_context *pcre2_compile_context;
+	const uint8_t *pcre2_tables;
 	uint32_t pcre2_jit_on;
 	unsigned fixed:1;
 	unsigned is_fixed:1;
@@ -172,6 +173,7 @@ struct grep_opt {
 void init_grep_defaults(struct repository *);
 int grep_config(const char *var, const char *value, void *);
 void grep_init(struct grep_opt *, struct repository *repo, const char *prefix);
+void grep_destroy(void);
 void grep_commit_pattern_type(enum grep_pattern_type, struct grep_opt *opt);
 
 void append_grep_pat(struct grep_opt *opt, const char *pat, size_t patlen, const char *origin, int no, enum grep_pat_token t);