[libc-commits] [libc] [libc][stdlib] Implement setenv() with environment management infrastructure (PR #163018)
Jeff Bailey via libc-commits
libc-commits at lists.llvm.org
Thu May 7 09:49:10 PDT 2026
https://github.com/kaladron updated https://github.com/llvm/llvm-project/pull/163018
>From f8d98bd8eeddd653b2e80893cafea4f3f158fc3a Mon Sep 17 00:00:00 2001
From: Jeff Bailey <jbailey at raspberryginger.com>
Date: Wed, 6 May 2026 20:14:37 +0100
Subject: [PATCH] [libc][stdlib] Add setenv, putenv, unsetenv
Added environment mutation functions using the EnvironmentManager
singleton. Each entrypoint validates inputs per POSIX and delegates to
a new manager method:
- set(name, value, overwrite): allocates "name=value", takes ownership.
- put(char *string): uses the caller string directly, no ownership.
Removes the variable if no '=' is present (glibc/musl convention).
- unset(name): frees the string if we own it, compacts the array.
Ownership is tracked per-string: set marks allocated_by_us = true, put
marks it false, and unset calls delete[] only when can_free() is true.
Registered for x86_64, aarch64, and riscv.
---
libc/config/linux/aarch64/entrypoints.txt | 3 +
libc/config/linux/riscv/entrypoints.txt | 3 +
libc/config/linux/x86_64/entrypoints.txt | 3 +
libc/include/stdlib.yaml | 20 +++
libc/src/stdlib/CMakeLists.txt | 22 +++
libc/src/stdlib/environ_internal.cpp | 113 +++++++++++++
libc/src/stdlib/environ_internal.h | 18 +++
libc/src/stdlib/linux/CMakeLists.txt | 44 +++++
libc/src/stdlib/linux/putenv.cpp | 33 ++++
libc/src/stdlib/linux/setenv.cpp | 48 ++++++
libc/src/stdlib/linux/unsetenv.cpp | 44 +++++
libc/src/stdlib/putenv.h | 25 +++
libc/src/stdlib/setenv.h | 25 +++
libc/src/stdlib/unsetenv.h | 25 +++
.../integration/src/stdlib/CMakeLists.txt | 39 +++++
.../integration/src/stdlib/putenv_test.cpp | 75 +++++++++
.../integration/src/stdlib/setenv_test.cpp | 153 ++++++++++++++++++
.../integration/src/stdlib/unsetenv_test.cpp | 91 +++++++++++
18 files changed, 784 insertions(+)
create mode 100644 libc/src/stdlib/linux/putenv.cpp
create mode 100644 libc/src/stdlib/linux/setenv.cpp
create mode 100644 libc/src/stdlib/linux/unsetenv.cpp
create mode 100644 libc/src/stdlib/putenv.h
create mode 100644 libc/src/stdlib/setenv.h
create mode 100644 libc/src/stdlib/unsetenv.h
create mode 100644 libc/test/integration/src/stdlib/putenv_test.cpp
create mode 100644 libc/test/integration/src/stdlib/setenv_test.cpp
create mode 100644 libc/test/integration/src/stdlib/unsetenv_test.cpp
diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index ea3f4cd8f51a0..4126ad1b54b15 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -1148,6 +1148,9 @@ if(LLVM_LIBC_FULL_BUILD)
libc.src.stdlib.atexit
libc.src.stdlib.exit
libc.src.stdlib.getenv
+ libc.src.stdlib.setenv
+ libc.src.stdlib.putenv
+ libc.src.stdlib.unsetenv
libc.src.stdlib.quick_exit
# signal.h entrypoints
diff --git a/libc/config/linux/riscv/entrypoints.txt b/libc/config/linux/riscv/entrypoints.txt
index d8d520c6d4236..ffc9cdafa33b9 100644
--- a/libc/config/linux/riscv/entrypoints.txt
+++ b/libc/config/linux/riscv/entrypoints.txt
@@ -1277,6 +1277,9 @@ if(LLVM_LIBC_FULL_BUILD)
libc.src.stdlib.atexit
libc.src.stdlib.exit
libc.src.stdlib.getenv
+ libc.src.stdlib.setenv
+ libc.src.stdlib.putenv
+ libc.src.stdlib.unsetenv
libc.src.stdlib.quick_exit
# signal.h entrypoints
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index dfd6064951d52..1402b48c5fb7e 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -1341,6 +1341,9 @@ if(LLVM_LIBC_FULL_BUILD)
libc.src.stdlib.atexit
libc.src.stdlib.exit
libc.src.stdlib.getenv
+ libc.src.stdlib.setenv
+ libc.src.stdlib.putenv
+ libc.src.stdlib.unsetenv
libc.src.stdlib.mbstowcs
libc.src.stdlib.mbtowc
libc.src.stdlib.quick_exit
diff --git a/libc/include/stdlib.yaml b/libc/include/stdlib.yaml
index a751f8306be24..2e922571fe6c9 100644
--- a/libc/include/stdlib.yaml
+++ b/libc/include/stdlib.yaml
@@ -172,6 +172,12 @@ functions:
- type: void **
- type: size_t
- type: size_t
+ - name: putenv
+ standards:
+ - posix
+ return_type: int
+ arguments:
+ - type: char *
- name: qsort
standards:
- stdc
@@ -209,6 +215,14 @@ functions:
return_type: void
arguments:
- type: unsigned int
+ - name: setenv
+ standards:
+ - posix
+ return_type: int
+ arguments:
+ - type: const char *
+ - type: const char *
+ - type: int
- name: strfromd
standards:
- stdc
@@ -355,6 +369,12 @@ functions:
return_type: int
arguments:
- type: const char *
+ - name: unsetenv
+ standards:
+ - posix
+ return_type: int
+ arguments:
+ - type: const char *
- name: wctomb
standards:
- stdc
diff --git a/libc/src/stdlib/CMakeLists.txt b/libc/src/stdlib/CMakeLists.txt
index 1185f1a0fa461..86af28a1d196c 100644
--- a/libc/src/stdlib/CMakeLists.txt
+++ b/libc/src/stdlib/CMakeLists.txt
@@ -81,6 +81,7 @@ add_object_library(
libc.src.__support.CPP.string_view
libc.src.__support.macros.attributes
libc.src.__support.macros.config
+ libc.src.string.memory_utils.inline_memcpy
)
add_entrypoint_object(
@@ -625,6 +626,27 @@ if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
endif()
+add_entrypoint_object(
+ setenv
+ ALIAS
+ DEPENDS
+ .${LIBC_TARGET_OS}.setenv
+)
+
+add_entrypoint_object(
+ putenv
+ ALIAS
+ DEPENDS
+ .${LIBC_TARGET_OS}.putenv
+)
+
+add_entrypoint_object(
+ unsetenv
+ ALIAS
+ DEPENDS
+ .${LIBC_TARGET_OS}.unsetenv
+)
+
if(LIBC_TARGET_OS_IS_BAREMETAL OR LIBC_TARGET_OS_IS_GPU)
add_entrypoint_object(
malloc
diff --git a/libc/src/stdlib/environ_internal.cpp b/libc/src/stdlib/environ_internal.cpp
index a6b630921f9f1..cf0ef617ed509 100644
--- a/libc/src/stdlib/environ_internal.cpp
+++ b/libc/src/stdlib/environ_internal.cpp
@@ -17,6 +17,7 @@
#include "src/__support/CPP/string_view.h"
#include "src/__support/alloc-checker.h"
#include "src/__support/macros/config.h"
+#include "src/string/memory_utils/inline_memcpy.h"
namespace LIBC_NAMESPACE_DECL {
namespace internal {
@@ -171,5 +172,117 @@ bool EnvironmentManager::ensure_capacity(size_t needed) {
return true;
}
+int EnvironmentManager::set(cpp::string_view name, cpp::string_view value,
+ bool overwrite) {
+ cpp::optional<size_t> idx = find_var(name);
+
+ // If the variable exists and we're not overwriting, do nothing.
+ if (idx && !overwrite)
+ return 0;
+
+ // Ensure we have capacity. If the variable doesn't exist, we need one
+ // more slot.
+ size_t needed = idx ? count : count + 1;
+ if (!ensure_capacity(needed))
+ return -1;
+
+ // Build the "name=value" string.
+ size_t name_len = name.size();
+ size_t value_len = value.size();
+ size_t total_len = name_len + 1 + value_len + 1; // name + '=' + value + '\0'
+
+ AllocChecker ac;
+ char *new_string = new (ac) char[total_len];
+ if (!ac)
+ return -1;
+
+ inline_memcpy(new_string, name.data(), name_len);
+ new_string[name_len] = '=';
+ inline_memcpy(new_string + name_len + 1, value.data(), value_len);
+ new_string[name_len + 1 + value_len] = '\0';
+
+ char **env_array = get_array();
+
+ if (idx) {
+ // Replace existing variable. Free old string if we own it.
+ if (ownership[*idx].can_free())
+ delete[] env_array[*idx];
+
+ env_array[*idx] = new_string;
+ ownership[*idx].allocated_by_us = true;
+ } else {
+ // Add new variable at the end.
+ env_array[count] = new_string;
+ ownership[count].allocated_by_us = true;
+ count++;
+ env_array[count] = nullptr; // Maintain null terminator.
+ }
+
+ return 0;
+}
+
+int EnvironmentManager::unset(cpp::string_view name) {
+ cpp::optional<size_t> idx = find_var(name);
+ if (!idx)
+ return 0; // Variable not found; POSIX defines this as success.
+
+ // Transition to managed storage so we can modify the array and track
+ // ownership correctly.
+ if (!ensure_capacity(count))
+ return -1;
+
+ char **env_array = get_array();
+
+ // Free the string if we allocated it.
+ if (ownership[*idx].can_free())
+ delete[] env_array[*idx];
+
+ // Compact: shift remaining entries left to fill the gap.
+ for (size_t i = *idx; i < count - 1; i++) {
+ env_array[i] = env_array[i + 1];
+ ownership[i] = ownership[i + 1];
+ }
+ count--;
+ env_array[count] = nullptr;
+
+ return 0;
+}
+
+int EnvironmentManager::put(char *string) {
+ cpp::string_view sv(string);
+ size_t eq_pos = sv.find_first_of('=');
+
+ // No '=' found: treat as unset (glibc/musl convention).
+ if (eq_pos == cpp::string_view::npos)
+ return unset(sv);
+
+ cpp::string_view name = sv.substr(0, eq_pos);
+
+ cpp::optional<size_t> idx = find_var(name);
+
+ size_t needed = idx ? count : count + 1;
+ if (!ensure_capacity(needed))
+ return -1;
+
+ char **env_array = get_array();
+
+ if (idx) {
+ // Replace existing variable. Free old string if we own it.
+ if (ownership[*idx].can_free())
+ delete[] env_array[*idx];
+
+ env_array[*idx] = string;
+ ownership[*idx].allocated_by_us = false; // Caller owns this string.
+ } else {
+ // Add new variable at the end.
+ env_array[count] = string;
+ ownership[count].allocated_by_us = false;
+ count++;
+ env_array[count] = nullptr;
+ }
+
+ return 0;
+}
+
} // namespace internal
} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/stdlib/environ_internal.h b/libc/src/stdlib/environ_internal.h
index 0ab75e200b968..c315f2d8626e0 100644
--- a/libc/src/stdlib/environ_internal.h
+++ b/libc/src/stdlib/environ_internal.h
@@ -122,6 +122,24 @@ class EnvironmentManager {
// Look up a variable by name. Returns a pointer to the value string
// (after the '='), or nullptr if not found.
char *get(cpp::string_view name);
+
+ // Set or update an environment variable. Builds a "name=value" string,
+ // manages ownership, and updates the environ array. If `overwrite` is
+ // false and the variable already exists, does nothing and returns 0.
+ // Returns 0 on success, -1 on allocation failure (caller should set
+ // errno to ENOMEM).
+ int set(cpp::string_view name, cpp::string_view value, bool overwrite);
+
+ // Insert a caller-provided "name=value" string into the environment.
+ // The caller retains ownership of the string; the manager will not
+ // free it. If string contains no '=', the named variable is removed
+ // (glibc/musl convention). Returns 0 on success, -1 on failure.
+ int put(char *string);
+
+ // Remove a variable by name. Frees the string if we own it, then
+ // compacts the array. Returns 0 on success (including if the variable
+ // was not found), -1 on allocation failure during array transition.
+ int unset(cpp::string_view name);
};
} // namespace internal
diff --git a/libc/src/stdlib/linux/CMakeLists.txt b/libc/src/stdlib/linux/CMakeLists.txt
index 8a4b2bab1c53d..c782548f2546a 100644
--- a/libc/src/stdlib/linux/CMakeLists.txt
+++ b/libc/src/stdlib/linux/CMakeLists.txt
@@ -8,3 +8,47 @@ add_header_library(
libc.src.signal.linux.__restore
libc.src.signal.linux.signal_utils
)
+
+add_entrypoint_object(
+ setenv
+ SRCS
+ setenv.cpp
+ HDRS
+ ../setenv.h
+ DEPENDS
+ libc.src.__support.CPP.string_view
+ libc.src.__support.common
+ libc.src.__support.libc_errno
+ libc.src.__support.macros.config
+ libc.src.__support.macros.null_check
+ libc.src.stdlib.environ_internal
+)
+
+add_entrypoint_object(
+ putenv
+ SRCS
+ putenv.cpp
+ HDRS
+ ../putenv.h
+ DEPENDS
+ libc.src.__support.common
+ libc.src.__support.libc_errno
+ libc.src.__support.macros.config
+ libc.src.__support.macros.null_check
+ libc.src.stdlib.environ_internal
+)
+
+add_entrypoint_object(
+ unsetenv
+ SRCS
+ unsetenv.cpp
+ HDRS
+ ../unsetenv.h
+ DEPENDS
+ libc.src.__support.CPP.string_view
+ libc.src.__support.common
+ libc.src.__support.libc_errno
+ libc.src.__support.macros.config
+ libc.src.__support.macros.null_check
+ libc.src.stdlib.environ_internal
+)
diff --git a/libc/src/stdlib/linux/putenv.cpp b/libc/src/stdlib/linux/putenv.cpp
new file mode 100644
index 0000000000000..3a499d6c0d1ba
--- /dev/null
+++ b/libc/src/stdlib/linux/putenv.cpp
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Implementation of the POSIX putenv function.
+///
+//===----------------------------------------------------------------------===//
+
+#include "src/stdlib/putenv.h"
+#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/null_check.h"
+#include "src/stdlib/environ_internal.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, putenv, (char *string)) {
+ LIBC_CRASH_ON_NULLPTR(string);
+
+ int result = internal::EnvironmentManager::get_instance().put(string);
+ if (result != 0)
+ libc_errno = ENOMEM;
+
+ return result;
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/stdlib/linux/setenv.cpp b/libc/src/stdlib/linux/setenv.cpp
new file mode 100644
index 0000000000000..f9c2075fb7787
--- /dev/null
+++ b/libc/src/stdlib/linux/setenv.cpp
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Implementation of the POSIX setenv function.
+///
+//===----------------------------------------------------------------------===//
+
+#include "src/stdlib/setenv.h"
+#include "src/__support/CPP/string_view.h"
+#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/null_check.h"
+#include "src/stdlib/environ_internal.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, setenv,
+ (const char *name, const char *value, int overwrite)) {
+ // Passing nullptr for either argument is undefined behavior per POSIX,
+ // so crash rather than returning an error.
+ LIBC_CRASH_ON_NULLPTR(name);
+ LIBC_CRASH_ON_NULLPTR(value);
+
+ cpp::string_view name_view(name);
+
+ // POSIX: name must not be empty or contain '='.
+ if (name_view.empty() || name_view.find_first_of('=') != cpp::string_view::npos) {
+ libc_errno = EINVAL;
+ return -1;
+ }
+
+ int result =
+ internal::EnvironmentManager::get_instance().set(name_view, value,
+ overwrite != 0);
+ if (result != 0)
+ libc_errno = ENOMEM;
+
+ return result;
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/stdlib/linux/unsetenv.cpp b/libc/src/stdlib/linux/unsetenv.cpp
new file mode 100644
index 0000000000000..129ea992d4c59
--- /dev/null
+++ b/libc/src/stdlib/linux/unsetenv.cpp
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Implementation of the POSIX unsetenv function.
+///
+//===----------------------------------------------------------------------===//
+
+#include "src/stdlib/unsetenv.h"
+#include "src/__support/CPP/string_view.h"
+#include "src/__support/common.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/config.h"
+#include "src/__support/macros/null_check.h"
+#include "src/stdlib/environ_internal.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, unsetenv, (const char *name)) {
+ LIBC_CRASH_ON_NULLPTR(name);
+
+ cpp::string_view name_view(name);
+
+ // POSIX: name must not be empty or contain '='.
+ if (name_view.empty() ||
+ name_view.find_first_of('=') != cpp::string_view::npos) {
+ libc_errno = EINVAL;
+ return -1;
+ }
+
+ int result =
+ internal::EnvironmentManager::get_instance().unset(name_view);
+ if (result != 0)
+ libc_errno = ENOMEM;
+
+ return result;
+}
+
+} // namespace LIBC_NAMESPACE_DECL
diff --git a/libc/src/stdlib/putenv.h b/libc/src/stdlib/putenv.h
new file mode 100644
index 0000000000000..1c07c5f80a61f
--- /dev/null
+++ b/libc/src/stdlib/putenv.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Declaration of the POSIX putenv function.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STDLIB_PUTENV_H
+#define LLVM_LIBC_SRC_STDLIB_PUTENV_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int putenv(char *string);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_STDLIB_PUTENV_H
diff --git a/libc/src/stdlib/setenv.h b/libc/src/stdlib/setenv.h
new file mode 100644
index 0000000000000..365d768cdd668
--- /dev/null
+++ b/libc/src/stdlib/setenv.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Declaration of the POSIX setenv function.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STDLIB_SETENV_H
+#define LLVM_LIBC_SRC_STDLIB_SETENV_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int setenv(const char *name, const char *value, int overwrite);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_STDLIB_SETENV_H
diff --git a/libc/src/stdlib/unsetenv.h b/libc/src/stdlib/unsetenv.h
new file mode 100644
index 0000000000000..b705d1b481aef
--- /dev/null
+++ b/libc/src/stdlib/unsetenv.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Declaration of the POSIX unsetenv function.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_STDLIB_UNSETENV_H
+#define LLVM_LIBC_SRC_STDLIB_UNSETENV_H
+
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int unsetenv(const char *name);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_STDLIB_UNSETENV_H
diff --git a/libc/test/integration/src/stdlib/CMakeLists.txt b/libc/test/integration/src/stdlib/CMakeLists.txt
index cf39b7ceb2f87..3c7285dc76c7f 100644
--- a/libc/test/integration/src/stdlib/CMakeLists.txt
+++ b/libc/test/integration/src/stdlib/CMakeLists.txt
@@ -17,6 +17,45 @@ add_integration_test(
GERMANY=Berlin
)
+if(${LIBC_TARGET_OS} STREQUAL "linux")
+ add_integration_test(
+ setenv_test
+ SUITE
+ stdlib-integration-tests
+ SRCS
+ setenv_test.cpp
+ DEPENDS
+ libc.src.stdlib.getenv
+ libc.src.stdlib.setenv
+ libc.src.string.strcmp
+ )
+
+ add_integration_test(
+ putenv_test
+ SUITE
+ stdlib-integration-tests
+ SRCS
+ putenv_test.cpp
+ DEPENDS
+ libc.src.stdlib.getenv
+ libc.src.stdlib.putenv
+ libc.src.string.strcmp
+ )
+
+ add_integration_test(
+ unsetenv_test
+ SUITE
+ stdlib-integration-tests
+ SRCS
+ unsetenv_test.cpp
+ DEPENDS
+ libc.src.stdlib.getenv
+ libc.src.stdlib.setenv
+ libc.src.stdlib.unsetenv
+ libc.src.string.strcmp
+ )
+endif()
+
if(${LIBC_TARGET_OS} STREQUAL "linux")
add_integration_test(
abort_test
diff --git a/libc/test/integration/src/stdlib/putenv_test.cpp b/libc/test/integration/src/stdlib/putenv_test.cpp
new file mode 100644
index 0000000000000..ad9305e3f80cc
--- /dev/null
+++ b/libc/test/integration/src/stdlib/putenv_test.cpp
@@ -0,0 +1,75 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/stdlib/getenv.h"
+#include "src/stdlib/putenv.h"
+#include "src/string/strcmp.h"
+
+#include "test/IntegrationTest/test.h"
+
+static char set_var[] = "PUTENV_TEST=hello";
+static char replace_var[] = "PUTENV_TEST=world";
+static char empty_value[] = "PUTENV_EMPTY=";
+static char special_chars[] = "PUTENV_SPECIAL=!@#$%^&*()";
+
+TEST_MAIN([[maybe_unused]] int argc, [[maybe_unused]] char **argv,
+ [[maybe_unused]] char **envp) {
+ // Test: Basic set
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::putenv(set_var), 0);
+ char *value = LIBC_NAMESPACE::getenv("PUTENV_TEST");
+ ASSERT_TRUE(value != nullptr);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(value, "hello"), 0);
+ }
+
+ // Test: Overwrite existing variable
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::putenv(replace_var), 0);
+ char *value = LIBC_NAMESPACE::getenv("PUTENV_TEST");
+ ASSERT_TRUE(value != nullptr);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(value, "world"), 0);
+ }
+
+ // Test: The pointer itself is used (not a copy)
+ {
+ // After putenv, getenv should return a pointer into the original string.
+ char *value = LIBC_NAMESPACE::getenv("PUTENV_TEST");
+ ASSERT_TRUE(value == replace_var + 12); // "PUTENV_TEST=" is 12 chars
+ }
+
+ // Test: Empty value
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::putenv(empty_value), 0);
+ char *value = LIBC_NAMESPACE::getenv("PUTENV_EMPTY");
+ ASSERT_TRUE(value != nullptr);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(value, ""), 0);
+ }
+
+ // Test: Special characters in value
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::putenv(special_chars), 0);
+ char *value = LIBC_NAMESPACE::getenv("PUTENV_SPECIAL");
+ ASSERT_TRUE(value != nullptr);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(value, "!@#$%^&*()"), 0);
+ }
+
+ // Test: No '=' removes the variable (glibc/musl convention)
+ {
+ // First set a variable via putenv
+ static char var_to_remove[] = "REMOVE_ME=present";
+ ASSERT_EQ(LIBC_NAMESPACE::putenv(var_to_remove), 0);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("REMOVE_ME") != nullptr);
+
+ // Now call putenv without '=' to remove it
+ static char remove_cmd[] = "REMOVE_ME";
+ ASSERT_EQ(LIBC_NAMESPACE::putenv(remove_cmd), 0);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("REMOVE_ME") == nullptr);
+ }
+
+ return 0;
+}
diff --git a/libc/test/integration/src/stdlib/setenv_test.cpp b/libc/test/integration/src/stdlib/setenv_test.cpp
new file mode 100644
index 0000000000000..4f9cc683433ab
--- /dev/null
+++ b/libc/test/integration/src/stdlib/setenv_test.cpp
@@ -0,0 +1,153 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/stdlib/getenv.h"
+#include "src/stdlib/setenv.h"
+#include "src/string/strcmp.h"
+
+#include "test/IntegrationTest/test.h"
+
+#include <errno.h>
+
+TEST_MAIN([[maybe_unused]] int argc, [[maybe_unused]] char **argv,
+ [[maybe_unused]] char **envp) {
+ // Test: Basic
+ {
+ // Set a simple environment variable
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("SETENV_TEST_VAR", "test_value", 1), 0);
+
+ // Verify it was set
+ char *value = LIBC_NAMESPACE::getenv("SETENV_TEST_VAR");
+ ASSERT_TRUE(value != nullptr);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(value, "test_value"), 0);
+ }
+
+ // Test: OverwriteExisting
+ {
+ // Set initial value
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("OVERWRITE_VAR", "original", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("OVERWRITE_VAR"),
+ "original"),
+ 0);
+
+ // Overwrite with new value (overwrite = 1)
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("OVERWRITE_VAR", "replaced", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("OVERWRITE_VAR"),
+ "replaced"),
+ 0);
+ }
+
+ // Test: NoOverwriteFlag
+ {
+ // Set initial value
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("NO_OVERWRITE_VAR", "original", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("NO_OVERWRITE_VAR"),
+ "original"),
+ 0);
+
+ // Try to set with overwrite = 0 (should not change)
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("NO_OVERWRITE_VAR", "ignored", 0), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("NO_OVERWRITE_VAR"),
+ "original"),
+ 0);
+
+ // Verify it still works with overwrite = 1
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("NO_OVERWRITE_VAR", "changed", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("NO_OVERWRITE_VAR"),
+ "changed"),
+ 0);
+ }
+
+ // Note: passing nullptr for name or value is undefined behavior per POSIX.
+ // The implementation uses LIBC_CRASH_ON_NULLPTR for both, so there is no
+ // test for that case here.
+
+ // Test: EmptyName
+ {
+ errno = 0;
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("", "value", 1), -1);
+ ASSERT_ERRNO_EQ(EINVAL);
+ }
+
+ // Test: NameWithEquals
+ {
+ errno = 0;
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("BAD=NAME", "value", 1), -1);
+ ASSERT_ERRNO_EQ(EINVAL);
+ }
+
+ // Test: EmptyValue
+ {
+ // Empty value is valid - just means variable is set to empty string
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("EMPTY_VALUE_VAR", "", 1), 0);
+
+ char *value = LIBC_NAMESPACE::getenv("EMPTY_VALUE_VAR");
+ ASSERT_TRUE(value != nullptr);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(value, ""), 0);
+ }
+
+ // Test: MultipleVariables
+ {
+ // Set multiple different variables
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("VAR1", "value1", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("VAR2", "value2", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("VAR3", "value3", 1), 0);
+
+ // Verify all are set correctly
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("VAR1"), "value1"),
+ 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("VAR2"), "value2"),
+ 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("VAR3"), "value3"),
+ 0);
+ }
+
+ // Test: LongValues
+ {
+ // Test with longer strings
+ const char *long_name = "LONG_VAR_NAME_FOR_TESTING";
+ const char *long_value = "This is a fairly long value string to test that "
+ "setenv handles longer strings correctly without "
+ "any memory issues or truncation problems";
+
+ ASSERT_EQ(LIBC_NAMESPACE::setenv(long_name, long_value, 1), 0);
+ ASSERT_EQ(
+ LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv(long_name), long_value),
+ 0);
+ }
+
+ // Test: SpecialCharacters
+ {
+ // Test with special characters in value (but not in name)
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("SPECIAL_CHARS", "!@#$%^&*()", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("SPECIAL_CHARS"),
+ "!@#$%^&*()"),
+ 0);
+ }
+
+ // Test: ReplaceMultipleTimes
+ {
+ // Replace the same variable multiple times
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("MULTI_REPLACE", "value1", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("MULTI_REPLACE"),
+ "value1"),
+ 0);
+
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("MULTI_REPLACE", "value2", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("MULTI_REPLACE"),
+ "value2"),
+ 0);
+
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("MULTI_REPLACE", "value3", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("MULTI_REPLACE"),
+ "value3"),
+ 0);
+ }
+
+ return 0;
+}
diff --git a/libc/test/integration/src/stdlib/unsetenv_test.cpp b/libc/test/integration/src/stdlib/unsetenv_test.cpp
new file mode 100644
index 0000000000000..b4d6aa0ce6c11
--- /dev/null
+++ b/libc/test/integration/src/stdlib/unsetenv_test.cpp
@@ -0,0 +1,91 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/stdlib/getenv.h"
+#include "src/stdlib/setenv.h"
+#include "src/stdlib/unsetenv.h"
+#include "src/string/strcmp.h"
+
+#include "test/IntegrationTest/test.h"
+
+#include <errno.h>
+
+TEST_MAIN([[maybe_unused]] int argc, [[maybe_unused]] char **argv,
+ [[maybe_unused]] char **envp) {
+ // Test: Remove a variable set by setenv
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("UNSET_VAR", "value", 1), 0);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("UNSET_VAR") != nullptr);
+
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("UNSET_VAR"), 0);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("UNSET_VAR") == nullptr);
+ }
+
+ // Test: Unset non-existent variable succeeds
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("DOES_NOT_EXIST"), 0);
+ }
+
+ // Test: Empty name returns EINVAL
+ {
+ errno = 0;
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv(""), -1);
+ ASSERT_ERRNO_EQ(EINVAL);
+ }
+
+ // Test: Name with '=' returns EINVAL
+ {
+ errno = 0;
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("BAD=NAME"), -1);
+ ASSERT_ERRNO_EQ(EINVAL);
+ }
+
+ // Test: Unset then re-set
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("REUSE_VAR", "first", 1), 0);
+ ASSERT_EQ(
+ LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("REUSE_VAR"), "first"),
+ 0);
+
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("REUSE_VAR"), 0);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("REUSE_VAR") == nullptr);
+
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("REUSE_VAR", "second", 1), 0);
+ ASSERT_EQ(
+ LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("REUSE_VAR"), "second"),
+ 0);
+ }
+
+ // Test: Unset multiple variables
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("MULTI_A", "a", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("MULTI_B", "b", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("MULTI_C", "c", 1), 0);
+
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("MULTI_B"), 0);
+
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("MULTI_A") != nullptr);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("MULTI_B") == nullptr);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("MULTI_C") != nullptr);
+
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("MULTI_A"), "a"),
+ 0);
+ ASSERT_EQ(LIBC_NAMESPACE::strcmp(LIBC_NAMESPACE::getenv("MULTI_C"), "c"),
+ 0);
+ }
+
+ // Test: Unset same variable twice is harmless
+ {
+ ASSERT_EQ(LIBC_NAMESPACE::setenv("DOUBLE_UNSET", "val", 1), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("DOUBLE_UNSET"), 0);
+ ASSERT_EQ(LIBC_NAMESPACE::unsetenv("DOUBLE_UNSET"), 0);
+ ASSERT_TRUE(LIBC_NAMESPACE::getenv("DOUBLE_UNSET") == nullptr);
+ }
+
+ return 0;
+}
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