core: add thread-safe strtok implementation (#3553)

This commit adds the support for a custom strtok implementation, which
is reentrant. On some systems strtok_r or strstep is available for that
purpose; however, since these are an extension, it is difficult to
control if it will be available on every supported system.

CMakeLists.txt

@@ -125,6 +125,7 @@ set(uv_sources
     src/inet.c
     src/random.c
     src/strscpy.c
+    src/strtok.c
     src/threadpool.c
     src/timer.c
     src/uv-common.c
@@ -562,6 +563,7 @@ if(LIBUV_BUILD_TESTS)
        test/test-spawn.c
        test/test-stdio-over-pipes.c
        test/test-strscpy.c
+       test/test-strtok.c
        test/test-tcp-alloc-cb-fail.c
        test/test-tcp-bind-error.c
        test/test-tcp-bind6-error.c

Makefile.am

@@ -43,7 +43,9 @@ libuv_la_SOURCES = src/fs-poll.c \
                    src/uv-data-getter-setters.c \
                    src/uv-common.c \
                    src/uv-common.h \
-                   src/version.c
+                   src/version.c \
+                   src/strtok.c \
+                   src/strtok.h
 
 if SUNOS
 # Can't be turned into a CC_CHECK_CFLAGS in configure.ac, it makes compilers
@@ -250,6 +252,7 @@ test_run_tests_SOURCES = test/blackhole-server.c \
                          test/test-spawn.c \
                          test/test-stdio-over-pipes.c \
                          test/test-strscpy.c \
+                         test/test-strtok.c \
                          test/test-tcp-alloc-cb-fail.c \
                          test/test-tcp-bind-error.c \
                          test/test-tcp-bind6-error.c \

src/strtok.c

@@ -0,0 +1,52 @@
+/* Copyright libuv project contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <stdlib.h>
+#include "strtok.h"
+
+char* uv__strtok(char* str, const char* sep, char** itr) {
+  const char* sep_itr;
+  char* tmp;
+  char* start;
+
+  if (str == NULL)
+    start = tmp = *itr;
+  else
+    start = tmp = str;
+
+  if (tmp == NULL)
+    return NULL;
+
+  while (*tmp != '\0') {
+    sep_itr = sep;
+    while (*sep_itr != '\0') {
+      if (*tmp == *sep_itr) {
+        *itr = tmp + 1;
+        *tmp = '\0';
+        return start;
+      }
+      sep_itr++;
+    }
+    tmp++;
+  }
+  *itr = NULL;
+  return start;
+}

src/strtok.h

@@ -0,0 +1,27 @@
+/* Copyright libuv project contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef UV_STRTOK_H_
+#define UV_STRTOK_H_
+
+char* uv__strtok(char* str, const char* sep, char** itr);
+
+#endif  /* UV_STRTOK_H_ */

src/unix/core.c

@@ -20,6 +20,7 @@
 
 #include "uv.h"
 #include "internal.h"
+#include "strtok.h"
 
 #include <stddef.h> /* NULL */
 #include <stdio.h> /* printf */
@@ -1546,6 +1547,7 @@ int uv__search_path(const char* prog, char* buf, size_t* buflen) {
   char* cloned_path;
   char* path_env;
   char* token;
+  char* itr;
 
   if (buf == NULL || buflen == NULL || *buflen == 0)
     return UV_EINVAL;
@@ -1587,7 +1589,7 @@ int uv__search_path(const char* prog, char* buf, size_t* buflen) {
   if (cloned_path == NULL)
     return UV_ENOMEM;
 
-  token = strtok(cloned_path, ":");
+  token = uv__strtok(cloned_path, ":", &itr);
   while (token != NULL) {
     snprintf(trypath, sizeof(trypath) - 1, "%s/%s", token, prog);
     if (realpath(trypath, abspath) == abspath) {
@@ -1606,7 +1608,7 @@ int uv__search_path(const char* prog, char* buf, size_t* buflen) {
         return 0;
       }
     }
-    token = strtok(NULL, ":");
+    token = uv__strtok(NULL, ":", &itr);
   }
   uv__free(cloned_path);
 

test/test-list.h

@@ -423,6 +423,7 @@ TEST_DECLARE   (fs_invalid_mkdir_name)
 #endif
 TEST_DECLARE   (fs_get_system_error)
 TEST_DECLARE   (strscpy)
+TEST_DECLARE   (strtok)
 TEST_DECLARE   (threadpool_queue_work_simple)
 TEST_DECLARE   (threadpool_queue_work_einval)
 TEST_DECLARE   (threadpool_multiple_event_loops)
@@ -1088,6 +1089,7 @@ TASK_LIST_START
   TEST_ENTRY  (get_osfhandle_valid_handle)
   TEST_ENTRY  (open_osfhandle_valid_handle)
   TEST_ENTRY  (strscpy)
+  TEST_ENTRY  (strtok)
   TEST_ENTRY  (threadpool_queue_work_simple)
   TEST_ENTRY  (threadpool_queue_work_einval)
   TEST_ENTRY_CUSTOM (threadpool_multiple_event_loops, 0, 0, 60000)

test/test-strtok.c

@@ -0,0 +1,90 @@
+/* Copyright libuv project contributors. All rights reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining a copy
+* of this software and associated documentation files (the "Software"), to
+* deal in the Software without restriction, including without limitation the
+* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+* sell copies of the Software, and to permit persons to whom the Software is
+* furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included in
+* all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+* IN THE SOFTWARE.
+*/
+
+#include "uv.h"
+#include "task.h"
+#include <string.h>
+
+#include "../src/strtok.h"
+#include "../src/strtok.c"
+
+struct strtok_test_case {
+  const char* str;
+  const char* sep;
+};
+
+const char* tokens[] = {
+  "abc",
+  NULL,
+
+  "abc",
+  "abf",
+  NULL,
+
+  "This",
+  "is.a",
+  "test",
+  "of",
+  "the",
+  "string",
+  "tokenizer",
+  "function.",
+  NULL,
+
+  "Hello",
+  "This-is-a-nice",
+  "-string",
+  NULL
+};
+
+#define ASSERT_STRCMP(x, y) \
+  ASSERT((x != NULL && y != NULL && strcmp(x, y) == 0) || (x == y && x == NULL))
+
+TEST_IMPL(strtok) {
+  struct strtok_test_case tests[] = {
+    { "abc", "" },
+    { "abc.abf", "." },
+    { "This;is.a:test:of=the/string\\tokenizer-function.", "\\/:;=-" },
+    { "Hello This-is-a-nice.-string", " ." },
+  };
+  size_t tokens_len = ARRAY_SIZE(tokens);
+  size_t tests_len = ARRAY_SIZE(tests);
+  size_t i;
+  size_t j;
+  char* itr;
+  char* tok_r;
+  char current_test[2048];
+
+  for (i = 0, j = 0; i < tests_len; i += 1) {
+    ASSERT(j < tokens_len);
+    snprintf(current_test, sizeof(current_test), "%s", tests[i].str);
+    tok_r = uv__strtok(current_test, tests[i].sep, &itr);
+    ASSERT_STRCMP(tok_r, tokens[j]);
+    j++;
+    while (tok_r) {
+      ASSERT(j < tokens_len);
+      tok_r = uv__strtok(NULL, tests[i].sep, &itr);
+      ASSERT_STRCMP(tok_r, tokens[j]);
+      j++;
+    }
+  }
+  return 0;
+}