Prefer std::regex over C regex_t

libs/pbd/file_utils.cc

@@ -24,6 +24,7 @@
 #include <climits>
 #include <set>
 #include <vector>
+#include <regex>
 
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
@@ -60,7 +61,6 @@
 #include <io.h> // Microsoft's nearest equivalent to <unistd.h>
 #include <ardourext/misc.h>
 #else
-#include <regex.h>
 #endif
 
 #include "pbd/compose.h"
@@ -243,8 +243,8 @@ static
 bool
 regexp_filter (const string& str, void *arg)
 {
-	regex_t* pattern = (regex_t*)arg;
+	std::regex* pattern = static_cast<std::regex*>(arg);
-	return regexec (pattern, str.c_str(), 0, 0, 0) == 0;
+	return std::regex_search(str, *pattern);
 }
 
 void
@@ -253,21 +253,11 @@ find_files_matching_regex (vector<string>& result,
                            const std::string& regexp,
                            bool recurse)
 {
-	int err;
+	std::regex compiled_pattern;
-	char msg[256];
+	try {
-	regex_t compiled_pattern;
+		compiled_pattern = std::regex(regexp);
-
+	} catch (const std::regex_error& e) {
-	if ((err = regcomp (&compiled_pattern, regexp.c_str(),
+		error << "Cannot compile soundfile regexp for use (" << e.what() << ")" << endmsg;
-			    REG_EXTENDED|REG_NOSUB))) {
-
-		regerror (err, &compiled_pattern,
-			  msg, sizeof (msg));
-
-		error << "Cannot compile soundfile regexp for use ("
-		      << msg
-		      << ")"
-		      << endmsg;
-
 		return;
 	}
 
@@ -277,8 +267,6 @@ find_files_matching_regex (vector<string>& result,
 	find_files_matching_filter (result, paths,
 	                            regexp_filter, &compiled_pattern,
 	                            true, true, recurse);
-
-	regfree (&compiled_pattern);
 }
 
 void

libs/pbd/pathexpand.cc

@@ -24,8 +24,7 @@
 #include <climits>
 #include <cerrno>
 #include <cstdlib>
-
+#include <regex>
-#include <regex.h>
 
 #include <glibmm/fileutils.h>
 #include <glibmm/miscutils.h>
@@ -42,69 +41,43 @@ using std::vector;
 string
 PBD::path_expand (string path)
 {
-        if (path.empty()) {
+	if (path.empty()) {
-                return path;
+		return path;
-        }
-
-        /* tilde expansion */
-
-        if (path[0] == '~') {
-                if (path.length() == 1) {
-                        return Glib::get_home_dir();
-                }
-
-                if (path[1] == '/') {
-                        path.replace (0, 1, Glib::get_home_dir());
-                } else {
-                        /* can't handle ~roger, so just leave it */
-                }
-        }
-
-	/* now do $VAR substitution, since wordexp isn't reliable */
-
-	regex_t compiled_pattern;
-	const int nmatches = 100;
-	regmatch_t matches[nmatches];
-
-	if (regcomp (&compiled_pattern, "\\$([a-zA-Z_][a-zA-Z0-9_]*|\\{[a-zA-Z_][a-zA-Z0-9_]*\\})", REG_EXTENDED)) {
-		std::cerr << "bad regcomp\n";
-                return path;
-        }
-
-	while (true) {
-
-		if (regexec (&compiled_pattern, path.c_str(), nmatches, matches, 0)) {
-			break;
-		}
-
-		/* matches[0] gives the entire match */
-
-		string match = path.substr (matches[0].rm_so, matches[0].rm_eo - matches[0].rm_so);
-
-		/* try to get match from the environment */
-
-                if (match[1] == '{') {
-                        /* ${FOO} form */
-                        match = match.substr (2, match.length() - 3);
-                }
-
-		char* matched_value = getenv (match.c_str());
-
-		if (matched_value) {
-			path.replace (matches[0].rm_so, matches[0].rm_eo - matches[0].rm_so, matched_value);
-		} else {
-			path.replace (matches[0].rm_so, matches[0].rm_eo - matches[0].rm_so, string());
-                }
-
-		/* go back and do it again with whatever remains after the
-		 * substitution
-		 */
 	}
 
-	regfree (&compiled_pattern);
+	/* tilde expansion */
+
+	if (path[0] == '~') {
+		if (path.length() == 1) {
+			return Glib::get_home_dir();
+		}
+
+		if (path[1] == '/') {
+			path.replace (0, 1, Glib::get_home_dir());
+		} else {
+			/* can't handle ~roger, so just leave it */
+		}
+	}
+
+	/* now do $VAR or ${VAR} substitution, since wordexp isn't reliable */
+
+	static const std::regex var_regex (R"(\$([A-Za-z_][A-Za-z0-9_]*|\{[A-Za-z_][A-Za-z0-9_]*\}))");
+
+	std::smatch m;
+
+	while (std::regex_search (path, m, var_regex)) {
+		std::string var = m[1].str(); // "$FOO" or "${FOO}"
+
+		if (var[0] == '{') {
+			var = var.substr(1, var.size() - 2);
+		}
+
+		const char* val = g_getenv (var.c_str());
+
+		path.replace (m.position(0), m.length(0), val ? val : "");
+	}
 
 	/* canonicalize */
-
 	return canonical_path (path);
 }
 

wscript

@@ -1227,10 +1227,6 @@ int main () { int x = SFC_RF64_AUTO_DOWNGRADE; return 0; }
             conf.env.append_value('LIB', 'uuid')
         # needed for mingw64 packages, not harmful on normal mingw build
         conf.env.append_value('LIB', 'intl')
-        conf.check_cc(function_name='regcomp', header_name='regex.h',
-                      lib='regex', uselib_store="REGEX", define_name='HAVE_REGEX_H')
-        # TODO put this only where it is needed
-        conf.env.append_value('LIB', 'regex')
         # TODO this should only be necessary for a debug build
         conf.env.append_value('LIB', 'dbghelp')