New Get_ENV Functions (#1141)

awslabs · Mar 4, 2025 · 568f46b · 568f46b
1 parent 9fd58f9
commit 568f46b
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diff --git a/include/aws/common/environment.h b/include/aws/common/environment.h
@@ -24,6 +24,22 @@ AWS_EXTERN_C_BEGIN
  * Not thread-safe
  */
 AWS_COMMON_API
+struct aws_string *aws_get_env(struct aws_allocator *allocator, const char *name);
+
+/*
+ * Get the value of an environment variable.  If the variable is not set or is empty, the output string will be set to
+ * NULL. Not thread-safe
+ */
+AWS_COMMON_API
+struct aws_string *aws_get_env_nonempty(struct aws_allocator *allocator, const char *name);
+
+/*
+ * *DEPRECATED*
+ * Please use the `aws_get_env` or `aws_get_env_nonempty` instead.
+ * Get the value of an environment variable.  If the variable is not set, the output string will be set to NULL.
+ * Not thread-safe
+ */
+AWS_COMMON_API
 int aws_get_environment_value(
     struct aws_allocator *allocator,
     const struct aws_string *variable_name,

diff --git a/source/posix/environment.c b/source/posix/environment.c
@@ -8,6 +8,26 @@
 #include <aws/common/string.h>
 #include <stdlib.h>
 
+struct aws_string *aws_get_env(struct aws_allocator *allocator, const char *name) {
+
+    const char *value = getenv(name);
+    if (value == NULL) {
+        return NULL;
+    }
+
+    return aws_string_new_from_c_str(allocator, value);
+}
+
+struct aws_string *aws_get_env_nonempty(struct aws_allocator *allocator, const char *name) {
+
+    const char *value = getenv(name);
+    if (value == NULL || value[0] == '\0') {
+        return NULL;
+    }
+
+    return aws_string_new_from_c_str(allocator, value);
+}
+
 int aws_get_environment_value(
     struct aws_allocator *allocator,
     const struct aws_string *variable_name,

diff --git a/source/windows/environment.c b/source/windows/environment.c
@@ -8,6 +8,40 @@
 
 #include <stdlib.h>
 
+struct aws_string *aws_get_env(struct aws_allocator *allocator, const char *name) {
+#ifdef _MSC_VER
+#    pragma warning(push)
+#    pragma warning(disable : 4996)
+#endif
+    const char *value = getenv(name);
+#ifdef _MSC_VER
+#    pragma warning(pop)
+#endif
+
+    if (value == NULL) {
+        return NULL;
+    }
+
+    return aws_string_new_from_c_str(allocator, value);
+}
+
+struct aws_string *aws_get_env_nonempty(struct aws_allocator *allocator, const char *name) {
+#ifdef _MSC_VER
+#    pragma warning(push)
+#    pragma warning(disable : 4996)
+#endif
+    const char *value = getenv(name);
+#ifdef _MSC_VER
+#    pragma warning(pop)
+#endif
+
+    if (value == NULL || value[0] == '\0') {
+        return NULL;
+    }
+
+    return aws_string_new_from_c_str(allocator, value);
+}
+
 int aws_get_environment_value(
     struct aws_allocator *allocator,
     const struct aws_string *variable_name,

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
@@ -391,6 +391,7 @@ add_test_case(uuid_string_parse_too_short)
 add_test_case(uuid_string_parse_malformed)
 
 add_test_case(test_environment_functions)
+add_test_case(test_env_functions)
 
 add_test_case(short_argument_parse)
 add_test_case(long_argument_parse)

diff --git a/tests/environment_test.c b/tests/environment_test.c
@@ -42,3 +42,43 @@ static int s_test_environment_functions_fn(struct aws_allocator *allocator, void
 }
 
 AWS_TEST_CASE(test_environment_functions, s_test_environment_functions_fn)
+
+static int s_test_env_functions_fn(struct aws_allocator *allocator, void *ctx) {
+    (void)ctx;
+
+    const char *env_name = aws_string_c_str(s_test_variable);
+    struct aws_string *value = aws_get_env(allocator, env_name);
+    ASSERT_TRUE(value == NULL);
+
+    value = aws_get_env_nonempty(allocator, env_name);
+    ASSERT_TRUE(value == NULL);
+
+    int result = aws_set_environment_value(s_test_variable, (struct aws_string *)s_test_value);
+    ASSERT_TRUE(result == AWS_OP_SUCCESS);
+
+    value = aws_get_env(allocator, env_name);
+    ASSERT_TRUE(aws_string_compare(value, s_test_value) == 0);
+    aws_string_destroy(value);
+
+    value = aws_get_env_nonempty(allocator, env_name);
+    ASSERT_TRUE(aws_string_compare(value, s_test_value) == 0);
+    aws_string_destroy(value);
+
+    struct aws_string *empty_str = aws_string_new_from_c_str(allocator, "");
+    result = aws_set_environment_value(s_test_variable, empty_str);
+    ASSERT_TRUE(result == AWS_OP_SUCCESS);
+
+    value = aws_get_env(allocator, env_name);
+#ifndef AWS_OS_WINDOWS
+    ASSERT_TRUE(aws_string_compare(value, empty_str) == 0);
+#endif
+    aws_string_destroy(value);
+
+    value = aws_get_env_nonempty(allocator, env_name);
+    ASSERT_TRUE(value == NULL);
+
+    aws_string_destroy(empty_str);
+    return AWS_OP_SUCCESS;
+}
+
+AWS_TEST_CASE(test_env_functions, s_test_env_functions_fn)