cross-compile library recipe in yocto - c

Question

I have a library with few source code files (.c) and header files and the output is shared library (.so).
Currently, i am using Makefile for generating .so
C = gcc
FLAGS = # -std=gnu99 -Iinclude
CFLAGS = -fPIC -g #-pedantic -Wall -Wextra -ggdb3
LDFLAGS = -shared
DEBUGFLAGS = -O0 -D _DEBUG
RELEASEFLAGS = -O2 -D NDEBUG -combine -fwhole-program
TARGET = libesys.so
SOURCES = $(wildcard *.c)
HEADERS = $(wildcard *.h)
OBJECTS = $(SOURCES:.c=.o)
all: $(TARGET)
$(TARGET): $(OBJECTS)
$(CC) $(FLAGS) $(CFLAGS) $(LDFLAGS) $(DEBUGFLAGS) -o $(TARGET) $(OBJECTS)
clean:
rm *.o libesys.so
I want to create a recipe in my meta layer to perform the above operation and generate .so when I do bitbake core-image-minimal. Can you please provide an example recipe which does similar operation.

Answer 1

First, have a look at simple recipe for a single source file from the dev-manual and try to first get a simple recipe building. You are correct in placing this recipe in your own meta layer.
Also have a look at this section that covers recipes with a Makefile.
Here is something to get you started
DESCRIPTION = "My test recipe"
LICENSE = "CLOSED"
PR = "r1"
S = "${WORKDIR}
FILES_${PN} = "libesys.so"
# Better to use a git repo for large projects
SRC_URI="file://xxxxxx \
file://yyyyyy \
"
do_install(){
oe_runmake install DESTDIR=${D} INCLUDEDIR=${includedir}
install -d ${D}${libdir}
install -m 0644 libesys.so ${D}${libdir}
}
BBCLASSEXTEND = "native"
You will also need to modify the core-image-minimal recipe to add a depends to your recipe so that it pulls in your lib.
DEPENDS+="your_recipe_name_here"
You can add this directly into the recipe itself, or add it via a .bbappends file that can reside in your layer.