Python tracing won't work when the shebang line has a space like below:

" #! /usr/bin/env python3 "

This patch makes uftrace to understand the above shebang as well.

Fixed: namhyung#1690
Signed-off-by: Gabriel Kim <[email protected]>

libmcount/dynamic.c

@@ -384,10 +384,17 @@ static bool match_pattern_module(char *pathname)
 	return ret;
 }
 
-static bool match_pattern_list(struct uftrace_mmap *map, char *soname, char *sym_name)
+/**
+ * match_pattern_list - match a symbol name against a pattern list
+ * @map - memory map of the symbol
+ * @soname - name of the module
+ * @sym_name - name of the symbol
+ * @return - -1 if match negative, 1 if match positive, 0 if no match
+ */
+static int match_pattern_list(struct uftrace_mmap *map, char *soname, char *sym_name)
 {
 	struct patt_list *pl;
-	bool ret = false;
+	int ret = 0;
 	char *libname = basename(map->libname);
 
 	list_for_each_entry(pl, &patterns, list) {
@@ -398,7 +405,7 @@ static bool match_pattern_list(struct uftrace_mmap *map, char *soname, char *sym
 			continue;
 
 		if (match_filter_pattern(&pl->patt, sym_name))
-			ret = pl->positive;
+			ret = pl->positive ? 1 : -1;
 	}
 
 	return ret;
@@ -410,7 +417,6 @@ static void parse_pattern_list(char *patch_funcs, char *def_mod, enum uftrace_pa
 	char *name;
 	int j;
 	struct patt_list *pl;
-	bool all_negative = true;
 
 	strv_split(&funcs, patch_funcs, ";");
 
@@ -421,10 +427,8 @@ static void parse_pattern_list(char *patch_funcs, char *def_mod, enum uftrace_pa
 
 		if (name[0] == '!')
 			name++;
-		else {
+		else
 			pl->positive = true;
-			all_negative = false;
-		}
 
 		delim = strchr(name, '@');
 		if (delim == NULL) {
@@ -439,20 +443,6 @@ static void parse_pattern_list(char *patch_funcs, char *def_mod, enum uftrace_pa
 		list_add_tail(&pl->list, &patterns);
 	}
 
-	/* prepend match-all pattern, if all patterns are negative */
-	if (all_negative) {
-		pl = xzalloc(sizeof(*pl));
-		pl->positive = true;
-		pl->module = xstrdup(def_mod);
-
-		if (ptype == PATT_REGEX)
-			init_filter_pattern(ptype, &pl->patt, ".");
-		else
-			init_filter_pattern(PATT_GLOB, &pl->patt, "*");
-
-		list_add(&pl->list, &patterns);
-	}
-
 	strv_free(&funcs);
 }
 
@@ -487,12 +477,6 @@ static bool skip_sym(struct uftrace_symbol *sym, struct mcount_dynamic_info *mdi
 	if (sym->type != ST_LOCAL_FUNC && sym->type != ST_GLOBAL_FUNC && sym->type != ST_WEAK_FUNC)
 		return true;
 
-	if (!match_pattern_list(map, soname, sym->name)) {
-		if (mcount_unpatch_func(mdi, sym, &disasm) == 0)
-			stats.unpatch++;
-		return true;
-	}
-
 	return false;
 }
 
@@ -559,6 +543,7 @@ static void patch_normal_func_matched(struct mcount_dynamic_info *mdi, struct uf
 	unsigned i;
 	struct uftrace_symbol *sym;
 	bool found = false;
+	int match;
 	char *soname = get_soname(map->libname);
 
 	symtab = &map->mod->symtab;
@@ -568,9 +553,15 @@ static void patch_normal_func_matched(struct mcount_dynamic_info *mdi, struct uf
 
 		if (skip_sym(sym, mdi, map, soname))
 			continue;
-
 		found = true;
-		mcount_patch_func_with_stats(mdi, sym);
+
+		match = match_pattern_list(map, soname, sym->name);
+		if (!match)
+			continue;
+		else if (match == 1)
+			mcount_patch_func_with_stats(mdi, sym);
+		else
+			mcount_unpatch_func(mdi, sym, NULL);
 	}
 
 	if (!found)
@@ -846,27 +837,27 @@ TEST_CASE(dynamic_pattern_list)
 	pr_dbg("check simple match with default module\n");
 	parse_pattern_list("abc;!def", "main", PATT_SIMPLE);
 
-	TEST_EQ(match_pattern_list(main_map, NULL, "abc"), true);
-	TEST_EQ(match_pattern_list(main_map, NULL, "def"), false);
-	TEST_EQ(match_pattern_list(other_map, NULL, "xyz"), false);
+	TEST_EQ(match_pattern_list(main_map, NULL, "abc"), 1);
+	TEST_EQ(match_pattern_list(main_map, NULL, "def"), -1);
+	TEST_EQ(match_pattern_list(other_map, NULL, "xyz"), 0);
 
 	release_pattern_list();
 
 	pr_dbg("check negative regex match with default module\n");
 	parse_pattern_list("!^a", "main", PATT_REGEX);
 
-	TEST_EQ(match_pattern_list(main_map, NULL, "abc"), false);
-	TEST_EQ(match_pattern_list(main_map, NULL, "def"), true);
-	TEST_EQ(match_pattern_list(other_map, NULL, "xyz"), false);
+	TEST_EQ(match_pattern_list(main_map, NULL, "abc"), -1);
+	TEST_EQ(match_pattern_list(main_map, NULL, "def"), 0);
+	TEST_EQ(match_pattern_list(other_map, NULL, "xyz"), 0);
 
 	release_pattern_list();
 
 	pr_dbg("check wildcard match with other module\n");
 	parse_pattern_list("*@other", "main", PATT_GLOB);
 
-	TEST_EQ(match_pattern_list(main_map, NULL, "abc"), false);
-	TEST_EQ(match_pattern_list(main_map, NULL, "def"), false);
-	TEST_EQ(match_pattern_list(other_map, NULL, "xyz"), true);
+	TEST_EQ(match_pattern_list(main_map, NULL, "abc"), 0);
+	TEST_EQ(match_pattern_list(main_map, NULL, "def"), 0);
+	TEST_EQ(match_pattern_list(other_map, NULL, "xyz"), 1);
 
 	release_pattern_list();
 

utils/utils.c

@@ -606,6 +606,7 @@ char *str_trim(char *str)
 		return NULL;
 	str = str_ltrim(str);
 	str = str_rtrim(str);
+	str = str_mtrim(str);
 	return str;
 }
 
@@ -640,6 +641,39 @@ char *str_rtrim(char *str)
 	return str;
 }
 
+/**
+ * str_mtrim - to trim middle spaces
+ * @str: input string
+ *
+ * This function make @str to middle trimmed @str
+ */
+char *str_mtrim(char *str)
+{
+	if (!str)
+		return NULL;
+
+	char *read_ptr = str;
+	char *write_ptr = str;
+	int space_flag = 0;
+
+	while (*read_ptr != '\0') {
+		if (isspace((unsigned char)*read_ptr)) {
+			if (!space_flag) {
+				*write_ptr++ = ' ';
+				space_flag = 1;
+			}
+		}
+		else {
+			*write_ptr++ = *read_ptr;
+			space_flag = 0;
+		}
+		read_ptr++;
+	}
+
+	*write_ptr = '\0';
+	return str;
+}
+
 /**
  * strv_split - split given string and construct a string vector
  * @strv:  string vector

utils/utils.h

@@ -392,6 +392,7 @@ void strv_free(struct strv *strv);
 char *str_trim(char *str);
 char *str_ltrim(char *str);
 char *str_rtrim(char *str);
+char *str_mtrim(char *str);
 
 char **parse_cmdline(char *cmd, int *argc);
 void free_parsed_cmdline(char **argv);