[libc][bazel] add targets to build the scanf family

[michaelrj-google]

Now that scanf is a little cleaner, this patch adds rules to build it
via bazel.

[llvmbot]

@llvm/pr-subscribers-libc

Author: Michael Jones (michaelrj-google)

Changes

Now that scanf is a little cleaner, this patch adds rules to build it
via bazel.

---

Full diff: https://github.com/llvm/llvm-project/pull/128082.diff

2 Files Affected:

• (modified) utils/bazel/llvm-project-overlay/libc/BUILD.bazel (+172)
• (modified) utils/bazel/llvm-project-overlay/libc/test/src/stdio/BUILD.bazel (+40)

diff --git a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
index b9847caa94f58..fb68144302c0e 100644
--- a/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/BUILD.bazel
@@ -4611,6 +4611,178 @@ libc_function(
     ],
 )
 
+libc_support_library(
+    name = "scanf_config",
+    hdrs = ["src/stdio/scanf_core/scanf_config.h"],
+    deps = [
+    ],
+)
+
+libc_support_library(
+    name = "scanf_core_structs",
+    hdrs = ["src/stdio/scanf_core/core_structs.h"],
+    deps = [
+        ":__support_cpp_bitset",
+        ":__support_cpp_string_view",
+        ":__support_fputil_fp_bits",
+        ":scanf_config",
+    ],
+)
+
+libc_support_library(
+    name = "scanf_parser",
+    hdrs = ["src/stdio/scanf_core/parser.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_cpp_bitset",
+        ":__support_ctype_utils",
+        ":__support_str_to_integer",
+        ":scanf_config",
+        ":scanf_core_structs",
+    ],
+)
+
+libc_support_library(
+    name = "scanf_reader",
+    hdrs = ["src/stdio/scanf_core/reader.h"],
+    deps = [
+        ":__support_cpp_string_view",
+        ":__support_macros_attributes",
+        ":types_FILE",
+    ],
+)
+
+libc_support_library(
+    name = "scanf_converter",
+    srcs = [
+        "src/stdio/scanf_core/converter.cpp",
+        "src/stdio/scanf_core/float_converter.cpp",
+        "src/stdio/scanf_core/int_converter.cpp",
+        "src/stdio/scanf_core/ptr_converter.cpp",
+        "src/stdio/scanf_core/string_converter.cpp",
+    ],
+    hdrs = [
+        "src/stdio/scanf_core/converter.h",
+        "src/stdio/scanf_core/converter_utils.h",
+        "src/stdio/scanf_core/current_pos_converter.h",
+        "src/stdio/scanf_core/float_converter.h",
+        "src/stdio/scanf_core/int_converter.h",
+        "src/stdio/scanf_core/ptr_converter.h",
+        "src/stdio/scanf_core/string_converter.h",
+    ],
+    deps = [
+        ":__support_char_vector",
+        ":__support_cpp_bitset",
+        ":__support_cpp_limits",
+        ":__support_cpp_string_view",
+        ":__support_ctype_utils",
+        ":__support_str_to_float",
+        ":scanf_core_structs",
+        ":scanf_reader",
+    ],
+)
+
+libc_support_library(
+    name = "scanf_main",
+    srcs = ["src/stdio/scanf_core/scanf_main.cpp"],
+    hdrs = ["src/stdio/scanf_core/scanf_main.h"],
+    deps = [
+        ":__support_arg_list",
+        ":scanf_config",
+        ":scanf_converter",
+        ":scanf_core_structs",
+        ":scanf_parser",
+        ":scanf_reader",
+    ],
+)
+
+libc_support_library(
+    name = "vfscanf_internal",
+    hdrs = ["src/stdio/scanf_core/vfscanf_internal.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":__support_macros_attributes",
+        ":scanf_main",
+        ":scanf_reader",
+        ":types_FILE",
+    ],
+)
+
+libc_function(
+    name = "scanf",
+    srcs = ["src/stdio/scanf.cpp"],
+    hdrs = ["src/stdio/scanf.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":types_FILE",
+        ":vfscanf_internal",
+    ],
+)
+
+libc_function(
+    name = "vscanf",
+    srcs = ["src/stdio/vscanf.cpp"],
+    hdrs = ["src/stdio/vscanf.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":types_FILE",
+        ":vfscanf_internal",
+    ],
+)
+
+libc_function(
+    name = "fscanf",
+    srcs = ["src/stdio/fscanf.cpp"],
+    hdrs = ["src/stdio/fscanf.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":types_FILE",
+        ":vfscanf_internal",
+    ],
+)
+
+libc_function(
+    name = "vfscanf",
+    srcs = ["src/stdio/vfscanf.cpp"],
+    hdrs = ["src/stdio/vfscanf.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":types_FILE",
+        ":vfscanf_internal",
+    ],
+)
+
+libc_function(
+    name = "sscanf",
+    srcs = ["src/stdio/sscanf.cpp"],
+    hdrs = ["src/stdio/sscanf.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":scanf_main",
+        ":scanf_reader",
+        ":types_FILE",
+    ],
+)
+
+libc_function(
+    name = "vsscanf",
+    srcs = ["src/stdio/vsscanf.cpp"],
+    hdrs = ["src/stdio/vsscanf.h"],
+    deps = [
+        ":__support_arg_list",
+        ":__support_file_file",
+        ":scanf_main",
+        ":scanf_reader",
+        ":types_FILE",
+    ],
+)
+
 libc_function(
     name = "remove",
     srcs = ["src/stdio/linux/remove.cpp"],
diff --git a/utils/bazel/llvm-project-overlay/libc/test/src/stdio/BUILD.bazel b/utils/bazel/llvm-project-overlay/libc/test/src/stdio/BUILD.bazel
index 145ef86380b62..c3865ea07ea91 100644
--- a/utils/bazel/llvm-project-overlay/libc/test/src/stdio/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/libc/test/src/stdio/BUILD.bazel
@@ -132,3 +132,43 @@ libc_test(
         "//libc:close",
     ],
 )
+
+libc_test(
+    name = "sscanf_test",
+    srcs = ["sscanf_test.cpp"],
+    libc_function_deps = [
+        "//libc:sscanf",
+    ],
+    deps = [
+        "//libc:__support_cpp_limits",
+        "//libc:__support_fputil_fp_bits",
+        "//libc:hdr_stdio_macros",
+        "//libc/test/UnitTest:fp_test_helpers",
+    ],
+)
+
+libc_test(
+    name = "fscanf_test",
+    srcs = ["fscanf_test.cpp"],
+    libc_function_deps = [
+        "//libc:fscanf",
+    ],
+    deps = ["//libc:__support_cpp_string_view"],
+)
+
+libc_test(
+    name = "vsscanf_test",
+    srcs = ["vsscanf_test.cpp"],
+    libc_function_deps = [
+        "//libc:vsscanf",
+    ],
+)
+
+libc_test(
+    name = "vfscanf_test",
+    srcs = ["vfscanf_test.cpp"],
+    libc_function_deps = [
+        "//libc:vfscanf",
+    ],
+    deps = ["//libc:__support_cpp_string_view"],
+)

[aaronmondal]

You might want to use the term targets instead of rules in the PR title. A rule would be something like the implementation of the binary_alias:

llvm-project/utils/bazel/llvm-project-overlay/llvm/binary_alias.bzl

Line 25 in 5e26fb1

binary_alias = rule(

The libc_support_library is in fact not a rule but a macro. You can see this because there is no rule keyword anywhere in its definition and instead it's effectively just a regular function defined via def:

llvm-project/utils/bazel/llvm-project-overlay/libc/libc_build_rules.bzl

Line 70 in 5e26fb1

def libc_support_library(name, **kwargs):

Ultimately this macro expands to targets, i.e. instantiations of the cc_library rule:

llvm-project/utils/bazel/llvm-project-overlay/libc/libc_build_rules.bzl

Line 58 in 5e26fb1

native.cc_library(

[michaelrj-google]

Thanks for the clarification