build: implement autotools build system for libopusfile. (v4)

Includes
- A make debug target that disables optimizations and enables
   assertions,
- Proper ./configure switches for the optional features,
- A configuration summary,
- libtool versioning information,
- Visibility and warning flags,
- API documentation, and
- Support for out-of-tree builds.
Signed-off-by: Diego Elio Pettenò <flameeyes@flameeyes.eu>

.gitignore

+*.la
+*.lo
+*.o
+*~
+.deps
+.dirstamp
+.libs
+/Makefile
+Makefile.in
+aclocal.m4
+autom4te.cache/
+config.guess
+config.log
+config.status
+config.sub
+configure
+depcomp
+examples/opusfile_example
+examples/seeking_example
+install-sh
+libopusfile-*.tar.*
+libtool
+ltmain.sh
+m4/libtool.m4
+m4/ltoptions.m4
+m4/ltsugar.m4
+m4/ltversion.m4
+m4/lt~obsolete.m4
+missing

Makefile.am

+ACLOCAL_AMFLAGS = -I m4
+
+AM_CFLAGS = -I$(top_srcdir)/include $(DEPS_CFLAGS)
+
+dist_doc_DATA = COPYING AUTHORS README.txt
+
+include_HEADERS = include/opusfile.h
+
+lib_LTLIBRARIES = libopusfile.la
+libopusfile_la_SOURCES = \
+	src/http.c src/info.c \
+	src/internal.c src/internal.h \
+	src/opusfile.c src/stream.c
+libopusfile_la_LIBADD = $(DEPS_LIBS)
+libopusfile_la_LDFLAGS = -no-undefined \
+ -version-info @OP_LT_CURRENT@:@OP_LT_REVISION@:@OP_LT_AGE@
+
+noinst_PROGRAMS = examples/opusfile_example examples/seeking_example
+
+examples_opusfile_example_LDADD = libopusfile.la
+examples_seeking_example_LDADD = libopusfile.la
+
+debug:
+	$(MAKE) CFLAGS="${CFLAGS} -O0 -ggdb -DOP_ENABLE_ASSERTIONS" all
+
+#API Documentation
+
+if HAVE_DOXYGEN
+
+EXTRA_DIST = doc/Doxyfile.in doc/git-version.sh
+
+all-local: doc/doxygen-build.stamp
+
+doc/doxygen-build.stamp: doc/Doxyfile $(top_srcdir)/include/*.h
+	cd doc && doxygen
+	touch "$@"
+
+install-data-local:
+	cd doc && for f in `find html -type f \! -name "installdox"` ; do \
+	  $(INSTALL_DATA) -D $$f $(DESTDIR)$(docdir)/$$f ; \
+	done
+
+clean-local:
+	$(RM) -r doc/html
+	$(RM) -r doc/latex
+	$(RM) doc/doxygen-build.stamp
+
+uninstall-local:
+	$(RM) -r $(DESTDIR)$(docdir)/html
+
+endif

autogen.sh

+#!/bin/sh
+# Run this to set up the build system: configure, makefiles, etc.
+set -e
+
+package="opusfile"
+
+ACLOCAL_FLAGS="-I m4"
+
+olddir=`pwd`
+srcdir=`dirname $0`
+test -z "$srcdir" && srcdir=.
+
+cd "$srcdir"
+
+echo "Updating build configuration files for $package, please wait...."
+autoreconf -is

configure.ac

+AC_INIT([libopusfile], [0.0])
+
+AC_USE_SYSTEM_EXTENSIONS
+AC_SYS_LARGEFILE
+
+AM_INIT_AUTOMAKE([1.11 foreign])
+LT_INIT
+
+m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
+
+AC_CONFIG_MACRO_DIR([m4])
+
+dnl Library versioning for libtool.
+dnl Please update these for releases.
+dnl CURRENT, REVISION, AGE
+dnl - library source changed -> increment REVISION
+dnl - interfaces added/removed/changed -> increment CURRENT, REVISION = 0
+dnl - interfaces added -> increment AGE
+dnl - interfaces removed -> AGE = 0
+
+OP_LT_CURRENT=0
+OP_LT_REVISION=0
+OP_LT_AGE=0
+
+AC_SUBST(OP_LT_CURRENT)
+AC_SUBST(OP_LT_REVISION)
+AC_SUBST(OP_LT_AGE)
+
+AC_ARG_ENABLE([assertions],
+  AS_HELP_STRING([--enable-assertions], [Enable assertions in code]),,
+  enable_assertions=no)
+
+AS_IF([test "x$enable_assertions" = "xyes"], [
+  AC_DEFINE([OP_ENABLE_ASSERTIONS], [1], [Enable assertions in code])
+])
+
+AC_ARG_ENABLE([http],
+  AS_HELP_STRING([--disable-http], [Disable HTTP support]),,
+  enable_http=yes)
+
+AS_IF([test "x$enable_http" != "xno"],
+  [openssl="openssl"
+   AC_DEFINE([OP_ENABLE_HTTP], [1], [Enable HTTP support])
+])
+
+PKG_CHECK_MODULES([DEPS], [ogg opus ]${openssl})
+
+AC_ARG_ENABLE([fixed-point],
+  AS_HELP_STRING([--enable-fixed-point], [Enable fixed-point calculation]),,
+  enable_fixed_point=no)
+AC_ARG_ENABLE([float],
+  AS_HELP_STRING([--disable-float], [Disable floating-point API]),,
+  enable_float=yes)
+
+AS_IF([test "x$enable_float" = "xno"],
+  [enable_fixed_point=yes
+   AC_DEFINE([OP_DISABLE_FLOAT_API], [1], [Disable floating-point API])
+  ]
+)
+
+AS_IF([test "x$enable_fixed_point" = "xyes"],
+  [AC_DEFINE([OP_FIXED_POINT], [1], [Enable fixed-point calculation])],
+  [dnl This only has to be tested for if float->fixed conversions are required
+   AC_SEARCH_LIBS([lrintf], [m], [
+      AC_DEFINE([OP_HAVE_LRINTF], [1], [Enable use of lrintf function])
+      lrintf_notice="
+  Library for lrintf() ....... : ${ac_cv_search_lrintf}"
+   ])
+  ]
+)
+
+CC_ATTRIBUTE_VISIBILITY([default], [
+  CC_FLAG_VISIBILITY([CFLAGS="${CFLAGS} -fvisibility=hidden"])
+])
+
+CC_CHECK_CFLAGS_APPEND([-std=c89 -pedantic -Wall -Wextra -Wno-parentheses -Wno-long-long])
+
+dnl Check for doxygen
+AC_ARG_ENABLE([doc],
+  AS_HELP_STRING([--disable-doc], [Do not build API documentation]),,
+  [enable_doc=yes]
+)
+
+if test "x$enable_doc" != "xno"; then
+  AC_CHECK_PROG(HAVE_DOXYGEN, doxygen, true, false)
+  if test "x$HAVE_DOXYGEN" = "xfalse" -a "x$enable_doc" = "xyes" ; then
+    AC_MSG_ERROR([*** Doxygen not found. Cannot build API documentation. ***])
+  fi
+else
+  HAVE_DOXYGEN=false
+fi
+AM_CONDITIONAL(HAVE_DOXYGEN,$HAVE_DOXYGEN)
+
+AC_OUTPUT([
+  Makefile
+  doc/Doxyfile
+])
+
+AC_MSG_NOTICE([
+Summary:
+
+Assertions ................... : ${enable_assertions}
+HTTP support ................. : ${enable_http}
+Fixed-point .................. : ${enable_fixed_point}
+Floating-point API ........... : ${enable_float}${lrintf_notice}
+Hidden visibility ............ : ${cc_cv_flag_visibility}
+API documentation ............ : ${enable_doc}
+])

doc/Doxyfile → doc/Doxyfile.in

 # Process with doxygen to generate API documentation
 
 PROJECT_NAME           = "opusfile"
-PROJECT_NUMBER         =
+PROJECT_NUMBER         = @VERSION@
 PROJECT_BRIEF          = "Stand alone decoder library for .opus files."
-INPUT                  = ../include/opusfile.h
+INPUT                  = @top_srcdir@/include/opusfile.h
 OPTIMIZE_OUTPUT_FOR_C  = YES
 
-FILE_VERSION_FILTER    = "/bin/sh git-version.sh"
+FILE_VERSION_FILTER    = "/bin/sh @top_srcdir@/doc/git-version.sh"
 
 QUIET                  = YES
 WARNINGS               = YES