shithub: libvpx

Download patch

ref: 7aa97a35b515bfb7d7bbcdee4db376f815343e44
parent: 9a27722b98ba58282efbf668864259139d4faa18
author: John Koleszar <jkoleszar@google.com>
date: Thu Jun 3 06:29:04 EDT 2010 

shared library support (.so)

This patch adds support for building shared libraries when configured
with the --enable-shared switch.

Building DLLs would require more invasive changes to the sample
utilities than I want to make in this patch, since on Windows you can't
use the address of an imported symbol in a static initializer. The best
way to work around this is proably to build the codec interface mapping
table with an init() function, but dll support is of questionable value
anyway, since most windows users will probably use a media framework
lib like webmdshow, which links this library in staticly.

Change-Id: Iafb48900549b0c6b67f4a05d3b790b2643d026f4


--- a/build/make/Makefile
+++ b/build/make/Makefile
@@ -220,6 +220,20 @@
 	$(qexec)$$(AR) $$(ARFLAGS) $$@ $$?
 endef
 
+define so_template
+# Not using a pattern rule here because we don't want to generate empty
+# archives when they are listed as a dependency in files not responsible
+# for creating them.
+#
+# This needs further abstraction for dealing with non-GNU linkers.
+$(1):
+	$(if $(quiet),@echo "    [LD] $$@")
+	$(qexec)$$(LD) -shared $$(LDFLAGS) \
+            -Wl,--no-undefined -Wl,-soname,$$(SONAME) \
+            -Wl,--version-script,$$(SO_VERSION_SCRIPT) -o $$@ \
+            $$(filter %.o,$$?)
+endef
+
 define lipo_lib_template
 $(1): $(addsuffix /$(1),$(FAT_ARCHS))
 	$(if $(quiet),@echo "    [LIPO] $$@")
@@ -283,6 +297,7 @@
 .libs: $(LIBS)
 	@touch $@
 $(foreach lib,$(filter %_g.a,$(LIBS)),$(eval $(call archive_template,$(lib))))
+$(foreach lib,$(filter %so.$(VERSION_MAJOR).$(VERSION_MINOR).$(VERSION_PATCH),$(LIBS)),$(eval $(call so_template,$(lib))))
 
 INSTALL-LIBS=$(call cond_enabled,CONFIG_INSTALL_LIBS,INSTALL-LIBS)
 ifeq ($(MAKECMDGOALS),dist)
--- a/configure
+++ b/configure
@@ -39,6 +39,7 @@
   ${toggle_spatial_resampling}    spatial sampling (scaling) support
   ${toggle_realtime_only}         enable this option while building for real-time encoding
   ${toggle_runtime_cpu_detect}    runtime cpu detection
+  ${toggle_shared}                shared library support
 
 Codecs:
   Codecs can be selectively enabled or disabled individually, or by family:
@@ -242,6 +243,7 @@
     static_msvcrt
     spatial_resampling
     realtime_only
+    shared
 "
 CMDLINE_SELECT="
     extra_warnings
@@ -280,6 +282,7 @@
     mem_tracker
     spatial_resampling
     realtime_only
+    shared
 "
 
 process_cmdline() {
@@ -369,6 +372,12 @@
     if [ -f "${source_path}/build/make/version.sh" ]; then
         local ver=`"$source_path/build/make/version.sh" --bare $source_path`
         DIST_DIR="${DIST_DIR}-${ver}"
+        ver=${ver%%-*}
+        VERSION_PATCH=${ver##*.}
+        ver=${ver%.*}
+        VERSION_MINOR=${ver##*.}
+        ver=${ver#v}
+        VERSION_MAJOR=${ver%.*}
     fi
     enabled child || cat <<EOF >> config.mk
 ifeq (\$(MAKECMDGOALS),dist)
@@ -377,6 +386,11 @@
 DIST_DIR?=\$(DESTDIR)${prefix}
 endif
 LIBSUBDIR=${libdir##${prefix}/}
+
+VERSION_MAJOR=${VERSION_MAJOR}
+VERSION_MINOR=${VERSION_MINOR}
+VERSION_PATCH=${VERSION_PATCH}
+
 EOF
     enabled child || echo "CONFIGURE_ARGS?=${CONFIGURE_ARGS}" >> config.mk
 
@@ -396,6 +410,12 @@
 }
 
 process_detect() {
+    if enabled shared; then
+        # Can only build shared libs on a subset of platforms. Doing this check
+        # here rather than at option parse time because the target auto-detect
+        # magic happens after the command line has been parsed.
+	enabled linux || die "--enable-shared only supported on ELF for now"
+    fi
     if [ -z "$CC" ]; then
         echo "Bypassing toolchain for environment detection."
         enable external_build
--- a/libs.mk
+++ b/libs.mk
@@ -92,7 +92,9 @@
 CODEC_SRCS-$(BUILD_LIBVPX) += vpx_ports/x86_abi_support.asm
 endif
 CODEC_SRCS-$(ARCH_ARM) += $(BUILD_PFX)vpx_config.asm
-CODEC_EXPORTS-$(BUILD_LIBVPX) += vpx/exports
+CODEC_EXPORTS-$(BUILD_LIBVPX) += vpx/exports_com
+CODEC_EXPORTS-$(CONFIG_ENCODERS) += vpx/exports_enc
+CODEC_EXPORTS-$(CONFIG_DECODERS) += vpx/exports_dec
 
 INSTALL-LIBS-yes += include/vpx/vpx_codec.h
 INSTALL-LIBS-yes += include/vpx/vpx_image.h
@@ -175,6 +177,31 @@
 OBJS-$(BUILD_LIBVPX) += $(LIBVPX_OBJS)
 LIBS-$(BUILD_LIBVPX) += $(BUILD_PFX)libvpx.a $(BUILD_PFX)libvpx_g.a
 $(BUILD_PFX)libvpx_g.a: $(LIBVPX_OBJS)
+
+BUILD_LIBVPX_SO         := $(if $(BUILD_LIBVPX),$(CONFIG_SHARED))
+LIBVPX_SO               := libvpx.so.$(VERSION_MAJOR).$(VERSION_MINOR).$(VERSION_PATCH)
+LIBS-$(BUILD_LIBVPX_SO) += $(BUILD_PFX)$(LIBVPX_SO)
+$(BUILD_PFX)$(LIBVPX_SO): $(LIBVPX_OBJS) libvpx.ver
+$(BUILD_PFX)$(LIBVPX_SO): LDFLAGS += -lm -pthread
+$(BUILD_PFX)$(LIBVPX_SO): SONAME = libvpx.so.$(VERSION_MAJOR)
+$(BUILD_PFX)$(LIBVPX_SO): SO_VERSION_SCRIPT = libvpx.ver
+LIBVPX_SO_SYMLINKS      := $(addprefix $(LIBSUBDIR)/, \
+                             libvpx.so libvpx.so.$(VERSION_MAJOR) \
+                             libvpx.so.$(VERSION_MAJOR).$(VERSION_MINOR))
+
+libvpx.ver: $(call enabled,CODEC_EXPORTS)
+	@echo "    [CREATE] $@"
+	$(qexec)echo "{ global:" > $@
+	$(qexec)for f in $?; do awk '{print $$2";"}' < $$f >>$@; done
+	$(qexec)echo "local: *; };" >> $@
+CLEAN-OBJS += libvpx.ver
+
+$(addprefix $(DIST_DIR)/,$(LIBVPX_SO_SYMLINKS)):
+	@echo "    [LN]      $@"
+	$(qexec)ln -sf $(LIBVPX_SO) $@
+
+INSTALL-LIBS-$(CONFIG_SHARED) += $(LIBVPX_SO_SYMLINKS)
+INSTALL-LIBS-$(CONFIG_SHARED) += $(LIBSUBDIR)/$(LIBVPX_SO)
 endif
 
 LIBS-$(LIPO_LIBVPX) += libvpx.a
--- /dev/null
+++ b/vp8/exports_dec
@@ -1,0 +1,1 @@
+data vpx_codec_vp8_dx_algo
--- /dev/null
+++ b/vp8/exports_enc
@@ -1,0 +1,1 @@
+data vpx_codec_vp8_cx_algo
--- a/vp8/vp8cx.mk
+++ b/vp8/vp8cx.mk
@@ -10,6 +10,9 @@
 
 
 include $(SRC_PATH_BARE)/$(VP8_PREFIX)vp8_common.mk
+
+VP8_CX_EXPORTS += exports_enc
+
 VP8_CX_SRCS-yes += $(VP8_COMMON_SRCS-yes)
 VP8_CX_SRCS-no  += $(VP8_COMMON_SRCS-no)
 VP8_CX_SRCS_REMOVE-yes += $(VP8_COMMON_SRCS_REMOVE-yes)
--- a/vp8/vp8dx.mk
+++ b/vp8/vp8dx.mk
@@ -10,6 +10,9 @@
 
 
 include $(SRC_PATH_BARE)/$(VP8_PREFIX)vp8_common.mk
+
+VP8_DX_EXPORTS += exports_dec
+
 VP8_DX_SRCS-yes += $(VP8_COMMON_SRCS-yes)
 VP8_DX_SRCS-no  += $(VP8_COMMON_SRCS-no)
 VP8_DX_SRCS_REMOVE-yes += $(VP8_COMMON_SRCS_REMOVE-yes)
--- a/vpx/exports
+++ /dev/null
@@ -1,17 +1,0 @@
-text vpx_dec_control
-text vpx_dec_decode
-text vpx_dec_destroy
-text vpx_dec_err_to_string
-text vpx_dec_error
-text vpx_dec_error_detail
-text vpx_dec_get_caps
-text vpx_dec_get_frame
-text vpx_dec_get_mem_map
-text vpx_dec_get_stream_info
-text vpx_dec_iface_name
-text vpx_dec_init_ver
-text vpx_dec_peek_stream_info
-text vpx_dec_register_put_frame_cb
-text vpx_dec_register_put_slice_cb
-text vpx_dec_set_mem_map
-text vpx_dec_xma_init_ver
--- /dev/null
+++ b/vpx/exports_com
@@ -1,0 +1,16 @@
+text vpx_codec_build_config
+text vpx_codec_control_
+text vpx_codec_destroy
+text vpx_codec_err_to_string
+text vpx_codec_error
+text vpx_codec_error_detail
+text vpx_codec_get_caps
+text vpx_codec_iface_name
+text vpx_codec_version
+text vpx_codec_version_extra_str
+text vpx_codec_version_str
+text vpx_img_alloc
+text vpx_img_flip
+text vpx_img_free
+text vpx_img_set_rect
+text vpx_img_wrap
--- /dev/null
+++ b/vpx/exports_dec
@@ -1,0 +1,9 @@
+text vpx_codec_dec_init_ver
+text vpx_codec_decode
+text vpx_codec_get_frame
+text vpx_codec_get_mem_map
+text vpx_codec_get_stream_info
+text vpx_codec_peek_stream_info
+text vpx_codec_register_put_frame_cb
+text vpx_codec_register_put_slice_cb
+text vpx_codec_set_mem_map
--- /dev/null
+++ b/vpx/exports_enc
@@ -1,0 +1,8 @@
+text vpx_codec_enc_config_default
+text vpx_codec_enc_config_set
+text vpx_codec_enc_init_ver
+text vpx_codec_encode
+text vpx_codec_get_cx_data
+text vpx_codec_get_global_headers
+text vpx_codec_get_preview_frame
+text vpx_codec_set_cx_data_buf