[libc] Add fopen_s.

bassiounix · bassiounix · commit 0466b6ace08f · 2025-08-06T08:02:30.000+03:00
diff --git a/libc/hdr/types/CMakeLists.txt b/libc/hdr/types/CMakeLists.txt
@@ -162,6 +162,24 @@ add_proxy_header_library(
     libc.include.fcntl
 )
 
+add_proxy_header_library(
+  errno_t
+  HDRS
+    errno_t.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.errno_t
+    libc.include.errno
+)
+
+add_proxy_header_library(
+  constraint_handler_t
+  HDRS
+    constraint_handler_t.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.constraint_handler_t
+    libc.include.stdlib
+)
+
 add_proxy_header_library(
   fenv_t
   HDRS
diff --git a/libc/hdr/types/constraint_handler_t.h b/libc/hdr/types/constraint_handler_t.h
@@ -0,0 +1,14 @@
+//===-- Proxy for constraint_handler_t ------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_HDR_TYPES_CONSTRAINT_HANDLER_T_H
+#define LLVM_LIBC_HDR_TYPES_CONSTRAINT_HANDLER_T_H
+
+#include "include/llvm-libc-types/constraint_handler_t.h"
+
+#endif // LLVM_LIBC_HDR_TYPES_CONSTRAINT_HANDLER_T_H
diff --git a/libc/hdr/types/errno_t.h b/libc/hdr/types/errno_t.h
@@ -0,0 +1,14 @@
+//===-- Proxy for errno_t -------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_HDR_TYPES_ERRNO_T_H
+#define LLVM_LIBC_HDR_TYPES_ERRNO_T_H
+
+#include "include/llvm-libc-types/errno_t.h"
+
+#endif // LLVM_LIBC_HDR_TYPES_ERRNO_T_H
diff --git a/libc/include/CMakeLists.txt b/libc/include/CMakeLists.txt
@@ -290,6 +290,7 @@ add_header_macro(
   DEPENDS
     .llvm-libc-macros.generic_error_number_macros
     .llvm-libc-macros.error_number_macros
+    .llvm-libc-types.errno_t
 )
 
 add_header_macro(
@@ -339,6 +340,7 @@ add_header_macro(
     .llvm-libc-types.off_t
     .llvm-libc-types.size_t
     .llvm-libc-types.ssize_t
+    .llvm-libc-types.errno_t
     .llvm_libc_common_h
 )
 
@@ -358,6 +360,7 @@ add_header_macro(
     .llvm-libc-types.lldiv_t
     .llvm-libc-types.locale_t
     .llvm-libc-types.size_t
+    .llvm-libc-types.constraint_handler_t
     .llvm_libc_common_h
 )
 
diff --git a/libc/include/errno.h.def b/libc/include/errno.h.def
@@ -33,4 +33,6 @@ __END_C_DECLS
 
 #define errno (*__llvm_libc_errno())
 
+#include "llvm-libc-types/errno_t.h"
+
 #endif // LLVM_LIBC_ERRNO_H
diff --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -289,3 +289,7 @@ add_header(EFI_SYSTEM_TABLE
     .EFI_TABLE_HEADER
     .char16_t
 )
+
+add_header(errno_t HDR errno_t.h)
+
+add_header(constraint_handler_t HDR constraint_handler_t.h DEPENDS .errno_t)
diff --git a/libc/include/llvm-libc-types/constraint_handler_t.h b/libc/include/llvm-libc-types/constraint_handler_t.h
@@ -0,0 +1,17 @@
+//===-- Definition of type constraint_handler_t ---------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_CONSTRAINT_HANDLER_T_H
+#define LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_CONSTRAINT_HANDLER_T_H
+
+#include "errno_t.h"
+
+typedef void (*constraint_handler_t)(const char *__restrict msg,
+                                     void *__restrict ptr, errno_t error);
+
+#endif // LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_CONSTRAINT_HANDLER_T_H
diff --git a/libc/include/llvm-libc-types/errno_t.h b/libc/include/llvm-libc-types/errno_t.h
@@ -0,0 +1,14 @@
+//===-- Definition of type errno_t ----------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
+#define LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
+
+typedef int errno_t;
+
+#endif // LLVM_LIBC_INCLUDE_LLVM_LIBC_TYPES_ERRNO_T_H
diff --git a/libc/include/stdio.yaml b/libc/include/stdio.yaml
@@ -11,6 +11,7 @@ macros:
     macro_value: stderr
 types:
   - type_name: size_t
+  - type_name: errno_t
   - type_name: off_t
   - type_name: cookie_io_functions_t
   - type_name: FILE
@@ -125,6 +126,14 @@ functions:
     arguments:
       - type: const char *
       - type: const char *
+  - name: fopen_s
+    standards:
+      - stdc
+    return_type: errno_t
+    arguments:
+      - type: FILE *__restrict *__restrict
+      - type: const char *__restrict
+      - type: const char *__restrict
   - name: fopencookie
     standards:
       - GNUExtensions
diff --git a/libc/include/stdlib.yaml b/libc/include/stdlib.yaml
@@ -17,6 +17,8 @@ types:
   - type_name: lldiv_t
   - type_name: locale_t
   - type_name: size_t
+  - type_name: errno_t
+  - type_name: constraint_handler_t
 enums: []
 objects: []
 functions:
@@ -180,6 +182,12 @@ functions:
     return_type: int
     arguments:
       - type: void
+  - name: set_constraint_handler_s
+    standards:
+      - stdc
+    return_type: constraint_handler_t
+    arguments:
+      - type: constraint_handler_t
   - name: srand
     standards:
       - stdc
diff --git a/libc/src/__support/CMakeLists.txt b/libc/src/__support/CMakeLists.txt
@@ -1,5 +1,7 @@
+add_subdirectory(annex_k)
 add_subdirectory(CPP)
 add_subdirectory(macros)
+add_subdirectory(stdio)
 
 add_header_library(
   libc_errno
diff --git a/libc/src/__support/annex_k/CMakeLists.txt b/libc/src/__support/annex_k/CMakeLists.txt
@@ -0,0 +1,40 @@
+add_header_library(
+  abort_handler_s
+  HDRS
+    abort_handler_s.h
+  DEPENDS
+    libc.hdr.stdio_macros
+    libc.hdr.types.errno_t
+    libc.src.__support.macros.config
+    libc.src.__support.macros.attributes
+    libc.src.__support.File.file
+    libc.src.stdio.fprintf
+    libc.src.stdio.fflush
+    libc.src.stdlib.abort
+)
+
+add_header_library(
+  ignore_handler_s
+  HDRS
+    ignore_handler_s.h
+  DEPENDS
+    libc.hdr.types.errno_t
+    libc.src.__support.libc_errno
+    libc.src.__support.macros.config
+    libc.src.__support.macros.attributes
+)
+
+add_header_library(
+  helper_macros
+  HDRS
+    helper_macros.h
+)
+
+add_header_library(
+  libc_constraint_handler
+  HDRS
+    libc_constraint_handler.h
+  DEPENDS
+    libc.src.__support.annex_k.abort_handler_s
+    libc.hdr.types.errno_t
+)
diff --git a/libc/src/__support/annex_k/abort_handler_s.h b/libc/src/__support/annex_k/abort_handler_s.h
@@ -0,0 +1,41 @@
+//===-- Implementation header for abort_handler_s ---------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_ANNEX_K_ABORT_HANDLER_S_H
+#define LLVM_LIBC_SRC___SUPPORT_ANNEX_K_ABORT_HANDLER_S_H
+
+#include "hdr/stdio_macros.h"
+#include "hdr/types/errno_t.h"
+#include "src/__support/libc_errno.h"
+#include "src/__support/macros/attributes.h"
+#include "src/__support/macros/config.h"
+#include "src/stdio/fflush.h"
+#include "src/stdio/fprintf.h"
+#include "src/stdlib/abort.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LIBC_INLINE static void abort_handler_s(const char *__restrict msg,
+                                        void *__restrict ptr, errno_t error) {
+  libc_errno = error;
+  fprintf(stderr, "abort_handler_s was called in response to a "
+                  "runtime-constraint violation.\n\n");
+  if (msg)
+    fprintf(stderr, "%s\n", msg);
+  fprintf(stderr,
+          "\n\nNote to end users: This program was terminated as a result\
+      of a bug present in the software. Please reach out to your  \
+      software's vendor to get more help.\n");
+
+  fflush(stderr);
+  abort();
+}
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_ANNEX_K_ABORT_HANDLER_S_H
diff --git a/libc/src/__support/annex_k/helper_macros.h b/libc/src/__support/annex_k/helper_macros.h
@@ -0,0 +1,43 @@
+//===-- Helper macros header for constraint violations ----------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_ANNEX_K_HELPER_MACROS_H
+#define LLVM_LIBC_SRC___SUPPORT_ANNEX_K_HELPER_MACROS_H
+
+#include "libc_constraint_hander.h"
+
+#define _CONSTRAINT_VIOLATION(msg, error_code, ret_code)                       \
+  {                                                                            \
+    libc_errno = error_code;                                                   \
+    libc_constraint_handler(msg, nullptr, error_code);                         \
+    return ret_code;                                                           \
+  }
+
+#define _CONSTRAINT_VIOLATION_IF(expr, error_code, return_code)                \
+  {                                                                            \
+    auto expr_val = expr;                                                      \
+    if (expr_val) {                                                            \
+      libc_errno = error_code;                                                 \
+      libc_constraint_handler(nullptr, nullptr, error_code);                   \
+      return return_code;                                                      \
+    }                                                                          \
+  }
+
+#define _CONSTRAINT_VIOLATION_CLEANUP_IF(expr, cleanup, error_code,            \
+                                         return_code)                          \
+  {                                                                            \
+    auto expr_val = expr;                                                      \
+    if (expr_val) {                                                            \
+      cleanup;                                                                 \
+      libc_errno = error_code;                                                 \
+      libc_constraint_handler(nullptr, nullptr, error_code);                   \
+      return return_code;                                                      \
+    }                                                                          \
+  }
+
+#endif // LLVM_LIBC_SRC___SUPPORT_ANNEX_K_HELPER_MACROS_H
diff --git a/libc/src/__support/annex_k/ignore_handler_s.h b/libc/src/__support/annex_k/ignore_handler_s.h
@@ -0,0 +1,23 @@
+//===-- Implementation header for ignore_handler_s --------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_ANNEX_K_IGNORE_HANDLER_S_H
+#define LLVM_LIBC_SRC___SUPPORT_ANNEX_K_IGNORE_HANDLER_S_H
+
+#include "hdr/types/errno_t.h"
+#include "src/__support/macros/attributes.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LIBC_INLINE static void ignore_handler_s(const char *__restrict msg,
+                                         void *__restrict ptr, errno_t error) {}
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_ANNEX_K_IGNORE_HANDLER_S_H
diff --git a/libc/src/__support/annex_k/libc_constraint_hander.h b/libc/src/__support/annex_k/libc_constraint_hander.h
@@ -0,0 +1,22 @@
+//===-- Static header for libc_constraint_handler ---------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_ANNEX_K_LIBC_CONSTRAINT_HANDER_H
+#define LLVM_LIBC_SRC___SUPPORT_ANNEX_K_LIBC_CONSTRAINT_HANDER_H
+
+#include "hdr/types/constraint_handler_t.h"
+#include "src/__support/annex_k/abort_handler_s.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LIBC_INLINE static constraint_handler_t libc_constraint_handler =
+    &abort_handler_s;
+
+}
+
+#endif // LLVM_LIBC_SRC___SUPPORT_ANNEX_K_LIBC_CONSTRAINT_HANDER_H
diff --git a/libc/src/__support/stdio/CMakeLists.txt b/libc/src/__support/stdio/CMakeLists.txt
@@ -0,0 +1,9 @@
+add_header_library(
+  fopen
+  HDRS
+    fopen.h
+  DEPENDS
+    libc.hdr.types.FILE
+    libc.src.__support.File.file
+    libc.src.__support.libc_errno
+)
diff --git a/libc/src/__support/stdio/fopen.h b/libc/src/__support/stdio/fopen.h
@@ -0,0 +1,34 @@
+//===-- Common implementation of fopen ------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC___SUPPORT_STDIO_FOPEN_H
+#define LLVM_LIBC_SRC___SUPPORT_STDIO_FOPEN_H
+
+#include "hdr/types/FILE.h"
+#include "src/__support/File/file.h"
+#include "src/__support/libc_errno.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+namespace stdio_internal {
+
+LIBC_INLINE static constexpr ::FILE *fopen(const char *__restrict name,
+                                           const char *__restrict mode) {
+  auto result = LIBC_NAMESPACE::openfile(name, mode);
+  if (!result.has_value()) {
+    libc_errno = result.error();
+    return nullptr;
+  }
+  return reinterpret_cast<::FILE *>(result.value());
+}
+
+} // namespace stdio_internal
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC___SUPPORT_STDIO_FOPEN_H
diff --git a/libc/src/stdio/CMakeLists.txt b/libc/src/stdio/CMakeLists.txt
diff --git a/libc/src/stdio/fopen_s.h b/libc/src/stdio/fopen_s.h
diff --git a/libc/src/stdio/generic/CMakeLists.txt b/libc/src/stdio/generic/CMakeLists.txt
diff --git a/libc/src/stdio/generic/fopen.cpp b/libc/src/stdio/generic/fopen.cpp
diff --git a/libc/src/stdio/generic/fopen_s.cpp b/libc/src/stdio/generic/fopen_s.cpp
diff --git a/libc/src/stdlib/CMakeLists.txt b/libc/src/stdlib/CMakeLists.txt
diff --git a/libc/src/stdlib/set_constraint_handler_s.cpp b/libc/src/stdlib/set_constraint_handler_s.cpp
diff --git a/libc/src/stdlib/set_constraint_handler_s.h b/libc/src/stdlib/set_constraint_handler_s.h

Original file line number	Diff line number	Diff line change
`@@ -290,6 +290,7 @@ add_header_macro(`
`290`	`290`	`DEPENDS`
`291`	`291`	`.llvm-libc-macros.generic_error_number_macros`
`292`	`292`	`.llvm-libc-macros.error_number_macros`
	`293`	`+ .llvm-libc-types.errno_t`
`293`	`294`	`)`
`294`	`295`
`295`	`296`	`add_header_macro(`
`@@ -339,6 +340,7 @@ add_header_macro(`
`339`	`340`	`.llvm-libc-types.off_t`
`340`	`341`	`.llvm-libc-types.size_t`
`341`	`342`	`.llvm-libc-types.ssize_t`
	`343`	`+ .llvm-libc-types.errno_t`
`342`	`344`	`.llvm_libc_common_h`
`343`	`345`	`)`
`344`	`346`
`@@ -358,6 +360,7 @@ add_header_macro(`
`358`	`360`	`.llvm-libc-types.lldiv_t`
`359`	`361`	`.llvm-libc-types.locale_t`
`360`	`362`	`.llvm-libc-types.size_t`
	`363`	`+ .llvm-libc-types.constraint_handler_t`
`361`	`364`	`.llvm_libc_common_h`
`362`	`365`	`)`
`363`	`366`
Original file line number	Diff line number	Diff line change
`@@ -289,3 +289,7 @@ add_header(EFI_SYSTEM_TABLE`
`289`	`289`	`.EFI_TABLE_HEADER`
`290`	`290`	`.char16_t`
`291`	`291`	`)`
	`292`	`+`
	`293`	`+add_header(errno_t HDR errno_t.h)`
	`294`	`+`
	`295`	`+add_header(constraint_handler_t HDR constraint_handler_t.h DEPENDS .errno_t)`