⁠Глава 12. Автоматизация сборки библиотек и версионирование

#include <stdio.h>
#include <stdlib.h>
#include "libinc.h"

int main(int argc, char *argv[]) {
        int n;

        if(argc < 2) {
          fprintf(stderr, "Usage: %s NUMBER\n", argv[0]);
          return 1;
        }

        n = atoi(argv[1]);
        printf("%d\n", inc(n));

 return 0;
}

#include "libinc.h"

int inc(int var) {
  return var + inc_var;
}

#include "libinc.h"
int inc_var = 1;

int inc(int);
extern int inc_var;

CFLAGS = -g -O
LTFLAGS = --tag=CC

all:    inc

%.lo:   %.c
       libtool --mode=compile $(LTFLAGS) $(CC) -c $<
libinc.la: fun.lo global.lo
       libtool --mode=link $(LTFLAGS) $(CC) -o $@ $^ -rpath /usr/lib64
inc:    main.o libinc.la
       libtool --mode=link $(LTFLAGS) $(CC) -o $@ $^
check:  inc
       test "`./$< 123`" = "124"
clean:
       rm -rf *.so inc .libs *.l? *.o

[user@VM inc-pkg]$ make
cc -g -O   -c -o main.o main.c
libtool --mode=compile --tag=CC cc -c fun.c
libtool-default: compile:  cc -c fun.c  -fPIC -DPIC -o .libs/fun.o
libtool-default: compile:  cc -c fun.c -o fun.o >/dev/null 2>&1
libtool --mode=compile --tag=CC cc -c global.c
libtool-default: compile:  cc -c global.c  -fPIC -DPIC -o .libs/global.o
libtool-default: compile:  cc -c global.c -o global.o >/dev/null 2>&1
libtool --mode=link --tag=CC cc -o libinc.la fun.lo global.lo -rpath /usr/lib64
libtool-default: link: x86_64-alt-linux-gcc -shared  -fPIC -DPIC  .libs/fun.o .libs/global.o      -Wl,-soname -Wl,libinc.so.0 -o .libs/libinc.so.0.0.0
libtool-default: link: (cd ".libs" && rm -f "libinc.so.0" && ln -s "libinc.so.0.0.0" "libinc.so.0")
libtool-default: link: (cd ".libs" && rm -f "libinc.so" && ln -s "libinc.so.0.0.0" "libinc.so")
libtool-default: link: ar cr .libs/libinc.a  fun.o global.o
libtool-default: link: ranlib .libs/libinc.a
libtool-default: link: ( cd ".libs" && rm -f "libinc.la" && ln -s "../libinc.la" "libinc.la" )
libtool --mode=link --tag=CC cc -o inc main.o libinc.la
libtool-default: link: cc -o .libs/inc main.o  ./.libs/libinc.so
[user@VM inc-pkg]$

.
├── fun.c
├── fun.lo
├── fun.o
├── global.c
├── global.lo
├── global.o
├── inc
├── libinc.h
├── libinc.la
├── main.c
├── main.o
└── Makefile
.libs/
├── fun.o
├── global.o
├── inc
├── libinc.a
├── libinc.la -> ../libinc.la
├── libinc.lai
├── libinc.so -> libinc.so.0.0.0
├── libinc.so.0 -> libinc.so.0.0.0
└── libinc.so.0.0.0

[user@VM inc-pkg]$ diff inc .libs/inc
Двоичные файлы inc и .libs/inc различаются
[user@VM inc-pkg]$ head -n1 inc
#! /bin/sh
[user@VM inc-pkg]$ grep "LD_LIBRARY_PATH" inc
relink_command="(cd /home/user/inc-pkg; { test -z \"\${LIBRARY_PATH+set}\" || unset LIBRARY_PATH || { LIBRARY_PATH=; export LIBRARY_PATH; }; }; { test -z \"\${COMPILER_PATH+set}\" || unset COMPILER_PA
TH || { COMPILER_PATH=; export COMPILER_PATH; }; }; { test -z \"\${GCC_EXEC_PREFIX+set}\" || unset GCC_EXEC_PREFIX || { GCC_EXEC_PREFIX=; export GCC_EXEC_PREFIX; }; }; { test -z \"\${LD_RUN_PATH+set}\" || unset
LD_RUN_PATH || { LD_RUN_PATH=; export LD_RUN_PATH; }; }; { test -z \"\${LD_LIBRARY_PATH+set}\" || unset LD_LIBRARY_PATH || { LD_LIBRARY_PATH=; export LD_LIBRARY_PATH; }; }; PATH=/home/user/.gemie/bin
:/home/user/bin:/usr/bin:/bin:/usr/local/bin:/usr/games; export PATH; cc -o \$progdir/\$file main.o  ./.libs/libinc.so -Wl,-rpath -Wl,/home/user/inc-pkg/.libs)"
[user@VM inc-pkg]$
[user@VM inc-pkg]$ ./inc 123
124
[user@VM inc-pkg]$ .libs/inc 123
.libs/inc: error while loading shared libraries: libinc.so.0: cannot open shared object file: No such file or directory
[user@VM inc-pkg]$ LD_LIBRARY_PATH=`pwd`/.libs .libs/inc 123
124
[user@VM inc-pkg]$

[user@VM inc-pkg]$ cat libinc.la
# libinc.la - a libtool library file
# Generated by libtool (GNU libtool) 2.4.7
#
# Please DO NOT delete this file!
# It is necessary for linking the library.

# The name that we can dlopen(3).
dlname='libinc.so.0'

# Names of this library.
library_names='libinc.so.0.0.0 libinc.so.0 libinc.so'

# The name of the static archive.
old_library='libinc.a'

# Linker flags that cannot go in dependency_libs.
inherited_linker_flags=''

# Libraries that this one depends upon.
dependency_libs=''

# Names of additional weak libraries provided by this library
weak_library_names=''

# Version information for libinc.
current=0
age=0
revision=0

# Is this an already installed library?
installed=no

# Should we warn about portability when linking against -modules?
shouldnotlink=no

# Files to dlopen/dlpreopen
dlopen=''
dlpreopen=''

# Directory that this library needs to be installed in:
libdir='/usr/lib64'
[user@VM inc-pkg]$ cat *.lo
# fun.lo - a libtool object file
# Generated by libtool (GNU libtool) 2.4.7
#
# Please DO NOT delete this file!
# It is necessary for linking the library.

# Name of the PIC object.
pic_object='.libs/fun.o'

# Name of the non-PIC object
non_pic_object='fun.o'

# global.lo - a libtool object file
# Generated by libtool (GNU libtool) 2.4.7
#
# Please DO NOT delete this file!
# It is necessary for linking the library.

# Name of the PIC object.
pic_object='.libs/global.o'

# Name of the non-PIC object
non_pic_object='global.o'

[user@VM inc-pkg]$