buildrootschalter/toolchain/toolchain-external/ext-toolchain-wrapper.c
Arnout Vandecappelle befb9a3ee0 Make external toolchain relocatable
The external toolchain wrapper sets sysroot etc. to an absolute path.
By changing this to a relative path, it is possible to move the host
directory to a different location and still have a working build
system.

This only works for a downloaded external toolchain.  For a pre-installed
external toolchain, it is possible to move the host directory to a
different location, but not the external toolchain directory (it does work
if the external toolchain directory lies within the host directory).  For
an internal or crosstool-ng toolchain, there is no wrapper so updating the
sysroot path should be done in a different way.

See http://lists.busybox.net/pipermail/buildroot/2012-February/050371.html
for information about others things to do to make the host directory
relocatable.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Acked-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
2013-02-05 15:06:31 +01:00

124 lines
2.8 KiB
C

/**
* Buildroot wrapper for external toolchains. This simply executes the real
* toolchain with a number of arguments (sysroot/arch/..) hardcoded,
* to ensure the external toolchain uses the correct configuration.
* The hardcoded path arguments are defined relative to the actual location
* of the binary.
*
* (C) 2011 Peter Korsgaard <jacmet@sunsite.dk>
* (C) 2011 Daniel Nyström <daniel.nystrom@timeterminal.se>
* (C) 2012 Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <unistd.h>
#include <stdlib.h>
static char path[PATH_MAX];
static char sysroot[PATH_MAX];
static char *predef_args[] = {
path,
"--sysroot", sysroot,
#ifdef BR_ARCH
"-march=" BR_ARCH,
#endif /* BR_ARCH */
#ifdef BR_TUNE
"-mtune=" BR_TUNE,
#endif /* BR_TUNE */
#ifdef BR_CPU
"-mcpu=" BR_CPU,
#endif
#ifdef BR_ABI
"-mabi=" BR_ABI,
#endif
#ifdef BR_SOFTFLOAT
"-msoft-float",
#endif /* BR_SOFTFLOAT */
#ifdef BR_VFPFLOAT
"-mfpu=vfp",
#endif /* BR_VFPFLOAT */
#ifdef BR_64
"-m64",
#endif
#ifdef BR_ADDITIONAL_CFLAGS
BR_ADDITIONAL_CFLAGS
#endif
};
int main(int argc, char **argv)
{
char **args, **cur;
char *relbasedir, *absbasedir;
char *progpath = argv[0];
char *basename;
int ret;
/* Calculate the relative paths */
basename = strrchr(progpath, '/');
if (basename) {
*basename = '\0';
basename++;
relbasedir = malloc(strlen(progpath) + 7);
if (relbasedir == NULL) {
perror(__FILE__ ": malloc");
return 2;
}
sprintf(relbasedir, "%s/../..", argv[0]);
absbasedir = realpath(relbasedir, NULL);
} else {
basename = progpath;
absbasedir = realpath("../..", NULL);
}
if (absbasedir == NULL) {
perror(__FILE__ ": realpath");
return 2;
}
/* Fill in the relative paths */
#ifdef BR_CROSS_PATH_REL
ret = snprintf(path, sizeof(path), "%s/" BR_CROSS_PATH_REL "/%s", absbasedir, basename);
#else /* BR_CROSS_PATH_ABS */
ret = snprintf(path, sizeof(path), BR_CROSS_PATH_ABS "/%s", basename);
#endif
if (ret >= sizeof(path)) {
perror(__FILE__ ": overflow");
return 3;
}
ret = snprintf(sysroot, sizeof(sysroot), "%s/" BR_SYSROOT, absbasedir);
if (ret >= sizeof(sysroot)) {
perror(__FILE__ ": overflow");
return 3;
}
cur = args = malloc(sizeof(predef_args) + (sizeof(char *) * argc));
if (args == NULL) {
perror(__FILE__ ": malloc");
return 2;
}
/* start with predefined args */
memcpy(cur, predef_args, sizeof(predef_args));
cur += sizeof(predef_args) / sizeof(predef_args[0]);
/* append forward args */
memcpy(cur, &argv[1], sizeof(char *) * (argc - 1));
cur += argc - 1;
/* finish with NULL termination */
*cur = NULL;
if (execv(path, args))
perror(path);
free(args);
return 2;
}