enh: Move CMake defines to separate header, unused by Bazel

This change avoids having to configure a private .h.in file during the Bazel build such that these files are not available to dependent projects in the GENDIR of the external gflags project.

CMakeLists.txt

@@ -352,6 +352,7 @@ else ()
 endif ()
 
 set (PRIVATE_HDRS
+  "defines.h"
   "config.h"
   "util.h"
   "mutex.h"

bazel/gflags.bzl

 # ------------------------------------------------------------------------------
 # Add native rules to configure source files
 def gflags_sources(namespace=["google", "gflags"]):
-    native.genrule(
-        name = "config_h",
-        srcs = ["src/config.h.in"],
-        outs = ["config.h"],
-        cmd  = "awk '{ gsub(/^#cmakedefine/, \"//cmakedefine\"); print; }' $(<) > $(@)"
-    )
     native.genrule(
         name = "gflags_declare_h",
         srcs = ["src/gflags_declare.h.in"],
-        outs = ["include/gflags/gflags_declare.h"],
+        outs = ["gflags_declare.h"],
         cmd  = ("awk '{ " +
                 "gsub(/@GFLAGS_NAMESPACE@/, \"" + namespace[0] + "\"); " +
                 "gsub(/@(HAVE_STDINT_H|HAVE_SYS_TYPES_H|HAVE_INTTYPES_H|GFLAGS_INTTYPES_FORMAT_C99)@/, \"1\"); " +
@@ -23,7 +17,7 @@ def gflags_sources(namespace=["google", "gflags"]):
         native.genrule(
             name = gflags_ns_h_file.replace('.', '_'),
             srcs = ["src/gflags_ns.h.in"],
-            outs = ["include/gflags/" + gflags_ns_h_file],
+            outs = [gflags_ns_h_file],
             cmd  = ("awk '{ " +
                     "gsub(/@ns@/, \"" + ns + "\"); " +
                     "gsub(/@NS@/, \"" + ns.upper() + "\"); " +
@@ -33,7 +27,7 @@ def gflags_sources(namespace=["google", "gflags"]):
     native.genrule(
         name = "gflags_h",
         srcs = ["src/gflags.h.in"],
-        outs = ["include/gflags/gflags.h"],
+        outs = ["gflags.h"],
         cmd  = ("awk '{ " +
                 "gsub(/@GFLAGS_ATTRIBUTE_UNUSED@/, \"\"); " +
                 "gsub(/@INCLUDE_GFLAGS_NS_H@/, \"" + '\n'.join(["#include \\\"gflags/{}\\\"".format(hdr) for hdr in gflags_ns_h_files]) + "\"); " +
@@ -42,13 +36,13 @@ def gflags_sources(namespace=["google", "gflags"]):
     native.genrule(
         name = "gflags_completions_h",
         srcs = ["src/gflags_completions.h.in"],
-        outs = ["include/gflags/gflags_completions.h"],
+        outs = ["gflags_completions.h"],
         cmd  = "awk '{ gsub(/@GFLAGS_NAMESPACE@/, \"" + namespace[0] + "\"); print; }' $(<) > $(@)"
     )
     hdrs = [":gflags_h", ":gflags_declare_h", ":gflags_completions_h"]
     hdrs.extend([':' + hdr.replace('.', '_') for hdr in gflags_ns_h_files])
     srcs = [
-        ":config_h",
+        "src/config.h",
         "src/gflags.cc",
         "src/gflags_completions.cc",
         "src/gflags_reporting.cc",
@@ -62,6 +56,10 @@ def gflags_sources(namespace=["google", "gflags"]):
 def gflags_library(hdrs=[], srcs=[], threads=1):
     name = "gflags"
     copts = [
+        "-DGFLAGS_BAZEL_BUILD",
+        "-DGFLAGS_INTTYPES_FORMAT_C99",
+        "-DGFLAGS_IS_A_DLL=0",
+        # macros otherwise defined by CMake configured defines.h file
         "-DHAVE_STDINT_H",
         "-DHAVE_SYS_TYPES_H",
         "-DHAVE_INTTYPES_H",
@@ -72,8 +70,6 @@ def gflags_library(hdrs=[], srcs=[], threads=1):
         "-DHAVE_STRTOQ",
         "-DHAVE_PTHREAD",
         "-DHAVE_RWLOCK",
-        "-DGFLAGS_INTTYPES_FORMAT_C99",
-        "-DGFLAGS_IS_A_DLL=0",
     ]
     linkopts = []
     if threads:
@@ -85,8 +81,8 @@ def gflags_library(hdrs=[], srcs=[], threads=1):
         name       = name,
         hdrs       = hdrs,
         srcs       = srcs,
-        includes   = ["include/"],
         copts      = copts,
         linkopts   = linkopts,
-        visibility = ["//visibility:public"]
+        visibility = ["//visibility:public"],
+        include_prefix = 'gflags'
     )

src/config.h.in → src/config.h

-/* Generated from config.h.in during build configuration using CMake. */
-
 // Note: This header file is only used internally. It is not part of public interface!
 
 #ifndef GFLAGS_CONFIG_H_
@@ -9,71 +7,16 @@
 // ---------------------------------------------------------------------------
 // System checks
 
-// Define if you build this library for a MS Windows OS.
-#cmakedefine OS_WINDOWS
-
-// Define if you have the <stdint.h> header file.
-#cmakedefine HAVE_STDINT_H
-
-// Define if you have the <sys/types.h> header file.
-#cmakedefine HAVE_SYS_TYPES_H
-
-// Define if you have the <inttypes.h> header file.
-#cmakedefine HAVE_INTTYPES_H
-
-// Define if you have the <sys/stat.h> header file.
-#cmakedefine HAVE_SYS_STAT_H
-
-// Define if you have the <unistd.h> header file.
-#cmakedefine HAVE_UNISTD_H
-
-// Define if you have the <fnmatch.h> header file.
-#cmakedefine HAVE_FNMATCH_H
-
-// Define if you have the <shlwapi.h> header file (Windows 2000/XP).
-#cmakedefine HAVE_SHLWAPI_H
-
-// Define if you have the strtoll function.
-#cmakedefine HAVE_STRTOLL
-
-// Define if you have the strtoq function.
-#cmakedefine HAVE_STRTOQ
-
-// Define if you have the <pthread.h> header file.
-#cmakedefine HAVE_PTHREAD
-
-// Define if your pthread library defines the type pthread_rwlock_t
-#cmakedefine HAVE_RWLOCK
+// CMake build configuration is written to defines.h file, unused by Bazel build
+#if !defined(GFLAGS_BAZEL_BUILD)
+#  include "defines.h"
+#endif
 
 // gcc requires this to get PRId64, etc.
 #if defined(HAVE_INTTYPES_H) && !defined(__STDC_FORMAT_MACROS)
 #  define __STDC_FORMAT_MACROS 1
 #endif
 
-// ---------------------------------------------------------------------------
-// Package information
-
-// Name of package.
-#define PACKAGE @PROJECT_NAME@
-
-// Define to the full name of this package.
-#define PACKAGE_NAME @PACKAGE_NAME@
-
-// Define to the full name and version of this package.
-#define PACKAGE_STRING @PACKAGE_STRING@
-
-// Define to the one symbol short name of this package.
-#define PACKAGE_TARNAME @PACKAGE_TARNAME@
-
-// Define to the version of this package.
-#define PACKAGE_VERSION @PACKAGE_VERSION@
-
-// Version number of package.
-#define VERSION PACKAGE_VERSION
-
-// Define to the address where bug reports for this package should be sent.
-#define PACKAGE_BUGREPORT @PACKAGE_BUGREPORT@
-
 // ---------------------------------------------------------------------------
 // Path separator
 #ifndef PATH_SEPARATOR

src/defines.h.in

+/* Generated from defines.h.in during build configuration using CMake. */
+
+// Note: This header file is only used internally. It is not part of public interface!
+//       Any cmakedefine is defined using the -D flag instead when Bazel is used.
+//       For Bazel, this file is thus not used to avoid a private file in $(GENDIR).
+
+#ifndef GFLAGS_DEFINES_H_
+#define GFLAGS_DEFINES_H_
+
+
+// Define if you build this library for a MS Windows OS.
+#cmakedefine OS_WINDOWS
+
+// Define if you have the <stdint.h> header file.
+#cmakedefine HAVE_STDINT_H
+
+// Define if you have the <sys/types.h> header file.
+#cmakedefine HAVE_SYS_TYPES_H
+
+// Define if you have the <inttypes.h> header file.
+#cmakedefine HAVE_INTTYPES_H
+
+// Define if you have the <sys/stat.h> header file.
+#cmakedefine HAVE_SYS_STAT_H
+
+// Define if you have the <unistd.h> header file.
+#cmakedefine HAVE_UNISTD_H
+
+// Define if you have the <fnmatch.h> header file.
+#cmakedefine HAVE_FNMATCH_H
+
+// Define if you have the <shlwapi.h> header file (Windows 2000/XP).
+#cmakedefine HAVE_SHLWAPI_H
+
+// Define if you have the strtoll function.
+#cmakedefine HAVE_STRTOLL
+
+// Define if you have the strtoq function.
+#cmakedefine HAVE_STRTOQ
+
+// Define if you have the <pthread.h> header file.
+#cmakedefine HAVE_PTHREAD
+
+// Define if your pthread library defines the type pthread_rwlock_t
+#cmakedefine HAVE_RWLOCK
+
+
+#endif // GFLAGS_DEFINES_H_