Added C API functions for compression args handling (w/ tests)

build.json

@@ -1365,6 +1365,20 @@
         "gpr"
       ]
     },
+    {
+      "name": "grpc_channel_args_test",
+      "build": "test",
+      "language": "c",
+      "src": [
+        "test/core/channel/channel_args_test.c"
+      ],
+      "deps": [
+        "grpc_test_util",
+        "grpc",
+        "gpr_test_util",
+        "gpr"
+      ]
+    },
     {
       "name": "grpc_channel_stack_test",
       "build": "test",

include/grpc/compression.h

@@ -36,12 +36,15 @@
 
 #include <stdlib.h>
 
+#include <grpc/support/port_platform.h>
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /** To be used in channel arguments */
 #define GRPC_COMPRESSION_ALGORITHM_ARG "grpc.compression_algorithm"
+#define GRPC_COMPRESSION_ALGORITHM_STATE_ARG "grpc.compression_algorithm_state"
 
 /* The various compression algorithms supported by GRPC */
 typedef enum {
@@ -60,6 +63,11 @@ typedef enum {
   GRPC_COMPRESS_LEVEL_COUNT
 } grpc_compression_level;
 
+typedef struct grpc_compression_options {
+  gpr_uint32 enabled_algorithms_bitset; /**< All algs are enabled by default */
+  grpc_compression_algorithm default_compression_algorithm; /**< for channel */
+} grpc_compression_options;
+
 /** Parses the first \a name_length bytes of \a name as a
  * grpc_compression_algorithm instance, updating \a algorithm. Returns 1 upon
  * success, 0 otherwise. */
@@ -67,9 +75,7 @@ int grpc_compression_algorithm_parse(const char *name, size_t name_length,
                                      grpc_compression_algorithm *algorithm);
 
 /** Updates \a name with the encoding name corresponding to a valid \a
- * algorithm. Note that the string returned through \a name upon success is
- * statically allocated and shouldn't be freed. Returns 1 upon success, 0
- * otherwise. */
+ * algorithm.  Returns 1 upon success, 0 otherwise. */
 int grpc_compression_algorithm_name(grpc_compression_algorithm algorithm,
                                     char **name);
 
@@ -85,6 +91,20 @@ grpc_compression_level grpc_compression_level_for_algorithm(
 grpc_compression_algorithm grpc_compression_algorithm_for_level(
     grpc_compression_level level);
 
+void grpc_compression_options_init(grpc_compression_options *opts);
+
+/** Mark \a algorithm as enabled in \a opts. */
+void grpc_compression_options_enable_algorithm(
+     grpc_compression_options *opts, grpc_compression_algorithm algorithm);
+
+/** Mark \a algorithm as disabled in \a opts. */
+void grpc_compression_options_disable_algorithm(
+    grpc_compression_options *opts, grpc_compression_algorithm algorithm);
+
+/** Returns true if \a algorithm is marked as enabled in \a opts. */
+int grpc_compression_options_is_algorithm_enabled(
+    const grpc_compression_options *opts, grpc_compression_algorithm algorithm);
+
 #ifdef __cplusplus
 }
 #endif

src/core/channel/channel_args.c

@@ -37,6 +37,7 @@
 
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
+#include <grpc/support/useful.h>
 
 #include <string.h>
 
@@ -146,3 +147,64 @@ grpc_channel_args *grpc_channel_args_set_compression_algorithm(
   tmp.value.integer = algorithm;
   return grpc_channel_args_copy_and_add(a, &tmp, 1);
 }
+
+/** Returns 1 if the argument for compression algorithm's enabled states bitset
+ * was found in \a a, returning the arg's value in \a states. Otherwise, returns
+ * 0. */
+static int find_compression_algorithm_states_bitset(
+    const grpc_channel_args *a, int **states_arg) {
+  if (a != NULL) {
+    size_t i;
+    for (i = 0; i < a->num_args; ++i) {
+      if (a->args[i].type == GRPC_ARG_INTEGER &&
+          !strcmp(GRPC_COMPRESSION_ALGORITHM_STATE_ARG, a->args[i].key)) {
+        *states_arg = &a->args[i].value.integer;
+        return 1; /* GPR_TRUE */
+      }
+    }
+  }
+  return 0; /* GPR_FALSE */
+}
+
+grpc_channel_args *grpc_channel_args_compression_algorithm_set_state(
+    grpc_channel_args *a,
+    grpc_compression_algorithm algorithm,
+    int state) {
+  int *states_arg;
+  grpc_channel_args *result = a;
+  const int states_arg_found =
+      find_compression_algorithm_states_bitset(a, &states_arg);
+
+  if (states_arg_found) {
+    if (state != 0) {
+      GPR_BITSET(states_arg, algorithm);
+    } else {
+      GPR_BITCLEAR(states_arg, algorithm);
+    }
+  } else {
+    /* create a new arg */
+    grpc_arg tmp;
+    tmp.type = GRPC_ARG_INTEGER;
+    tmp.key = GRPC_COMPRESSION_ALGORITHM_STATE_ARG;
+    /* all enabled by default */
+    tmp.value.integer = (1u << GRPC_COMPRESS_ALGORITHMS_COUNT) - 1;
+    if (state != 0) {
+      GPR_BITSET(&tmp.value.integer, algorithm);
+    } else {
+      GPR_BITCLEAR(&tmp.value.integer, algorithm);
+    }
+    result = grpc_channel_args_copy_and_add(a, &tmp, 1);
+    grpc_channel_args_destroy(a);
+  }
+  return result;
+}
+
+int grpc_channel_args_compression_algorithm_get_states(
+    const grpc_channel_args *a) {
+  int *states_arg;
+  if (find_compression_algorithm_states_bitset(a, &states_arg)) {
+    return *states_arg;
+  } else {
+    return (1u << GRPC_COMPRESS_ALGORITHMS_COUNT) - 1; /* All algs. enabled */
+  }
+}

src/core/channel/channel_args.h

@@ -67,4 +67,21 @@ grpc_compression_algorithm grpc_channel_args_get_compression_algorithm(
 grpc_channel_args *grpc_channel_args_set_compression_algorithm(
     grpc_channel_args *a, grpc_compression_algorithm algorithm);
 
+/** Sets the support for the given compression algorithm. By default, all
+ * compression algorithms are enabled. It's an error to disable an algorithm set
+ * by grpc_channel_args_set_compression_algorithm.
+ * */
+grpc_channel_args *grpc_channel_args_compression_algorithm_set_state(
+    grpc_channel_args *a,
+    grpc_compression_algorithm algorithm,
+    int enabled);
+
+/** Returns the bitset representing the support state (true for enabled, false
+ * for disabled) for compression algorithms.
+ *
+ * The i-th bit of the returned bitset corresponds to the i-th entry in the
+ * grpc_compression_algorithm enum. */
+int grpc_channel_args_compression_algorithm_get_states(
+    const grpc_channel_args *a);
+
 #endif /* GRPC_INTERNAL_CORE_CHANNEL_CHANNEL_ARGS_H */

test/core/channel/channel_args_test.c

@@ -0,0 +1,136 @@
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <string.h>
+
+#include <grpc/support/log.h>
+#include <grpc/support/useful.h>
+
+#include "src/core/channel/channel_args.h"
+
+#include "test/core/util/test_config.h"
+
+static void test_create(void) {
+  grpc_arg arg_int;
+  grpc_arg arg_string;
+  grpc_arg to_add[2];
+  grpc_channel_args *ch_args;
+  
+  arg_int.key = "int_arg";
+  arg_int.type = GRPC_ARG_INTEGER;
+  arg_int.value.integer = 123;
+
+  arg_string.key = "str key";
+  arg_string.type = GRPC_ARG_STRING;
+  arg_string.value.string = "str value";
+
+  to_add[0] = arg_int;
+  to_add[1] = arg_string;
+  ch_args = grpc_channel_args_copy_and_add(NULL, to_add, 2);
+  
+  GPR_ASSERT(ch_args->num_args == 2);
+  GPR_ASSERT(strcmp(ch_args->args[0].key, arg_int.key) == 0);
+  GPR_ASSERT(ch_args->args[0].type == arg_int.type);
+  GPR_ASSERT(ch_args->args[0].value.integer == arg_int.value.integer);
+
+  GPR_ASSERT(strcmp(ch_args->args[1].key, arg_string.key) == 0);
+  GPR_ASSERT(ch_args->args[1].type == arg_string.type);
+  GPR_ASSERT(strcmp(ch_args->args[1].value.string, arg_string.value.string) ==
+             0);
+
+  grpc_channel_args_destroy(ch_args);
+}
+
+static void test_set_compression_algorithm(void) {
+  grpc_channel_args *ch_args;
+
+  ch_args =
+      grpc_channel_args_set_compression_algorithm(NULL, GRPC_COMPRESS_GZIP);
+  GPR_ASSERT(ch_args->num_args == 1);
+  GPR_ASSERT(strcmp(ch_args->args[0].key, GRPC_COMPRESSION_ALGORITHM_ARG) == 0);
+  GPR_ASSERT(ch_args->args[0].type == GRPC_ARG_INTEGER);
+
+  grpc_channel_args_destroy(ch_args);
+}
+
+static void test_compression_algorithm_states(void) {
+  grpc_channel_args *ch_args;
+  int states_bitset;
+  size_t i;
+
+  ch_args = grpc_channel_args_copy_and_add(NULL, NULL, 0);
+  /* by default, all enabled */
+  states_bitset = grpc_channel_args_compression_algorithm_get_states(ch_args);
+
+  for (i = 0; i < GRPC_COMPRESS_ALGORITHMS_COUNT; i++) {
+    GPR_ASSERT(GPR_BITGET(states_bitset, i));
+  }
+
+  /* disable gzip and deflate */
+  ch_args = grpc_channel_args_compression_algorithm_set_state(
+      ch_args, GRPC_COMPRESS_GZIP, 0);
+  ch_args = grpc_channel_args_compression_algorithm_set_state(
+      ch_args, GRPC_COMPRESS_DEFLATE, 0);
+
+  states_bitset = grpc_channel_args_compression_algorithm_get_states(ch_args);
+  for (i = 0; i < GRPC_COMPRESS_ALGORITHMS_COUNT; i++) {
+    if (i == GRPC_COMPRESS_GZIP || i == GRPC_COMPRESS_DEFLATE) {
+      GPR_ASSERT(GPR_BITGET(states_bitset, i) == 0);
+    } else {
+      GPR_ASSERT(GPR_BITGET(states_bitset, i) != 0);
+    }
+  }
+
+  /* re-enabled gzip only */
+  ch_args = grpc_channel_args_compression_algorithm_set_state(
+      ch_args, GRPC_COMPRESS_GZIP, 1);
+
+  states_bitset = grpc_channel_args_compression_algorithm_get_states(ch_args);
+  for (i = 0; i < GRPC_COMPRESS_ALGORITHMS_COUNT; i++) {
+    if (i == GRPC_COMPRESS_DEFLATE) {
+      GPR_ASSERT(GPR_BITGET(states_bitset, i) == 0);
+    } else {
+      GPR_ASSERT(GPR_BITGET(states_bitset, i) != 0);
+    }
+  }
+
+  grpc_channel_args_destroy(ch_args);
+}
+
+int main(int argc, char **argv) {
+  grpc_test_init(argc, argv);
+  test_create();
+  test_set_compression_algorithm();
+  test_compression_algorithm_states();
+  return 0;
+}

tools/run_tests/sources_and_headers.json

@@ -459,6 +459,20 @@
       "test/core/surface/byte_buffer_reader_test.c"
     ]
   }, 
+  {
+    "deps": [
+      "gpr", 
+      "gpr_test_util", 
+      "grpc", 
+      "grpc_test_util"
+    ], 
+    "headers": [], 
+    "language": "c", 
+    "name": "grpc_channel_args_test", 
+    "src": [
+      "test/core/channel/channel_args_test.c"
+    ]
+  }, 
   {
     "deps": [
       "gpr", 

tools/run_tests/tests.json

@@ -567,6 +567,24 @@
       "windows"
     ]
   }, 
+  {
+    "ci_platforms": [
+      "linux", 
+      "mac", 
+      "posix", 
+      "windows"
+    ], 
+    "exclude_configs": [], 
+    "flaky": false, 
+    "language": "c", 
+    "name": "grpc_channel_args_test", 
+    "platforms": [
+      "linux", 
+      "mac", 
+      "posix", 
+      "windows"
+    ]
+  }, 
   {
     "ci_platforms": [
       "linux", 
@@ -1538,6 +1556,7 @@
       "posix", 
       "windows"
     ], 
+    "exclude_configs": [], 
     "flaky": false, 
     "language": "c++", 
     "name": "status_test",