nixpkgs/pkgs/development/skaware-packages/execline/execlineb-wrapper.c

52 lines
1.4 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* A wrapper around execlineb, which provides all execline
* tools on execlinebs PATH.
* It is implemented as a C program, because on non-Linux,
* nested shebang lines are not supported.
*/
#include <stdlib.h>
#include <string.h>
#include <skalibs/stralloc.h>
#include <skalibs/djbunix.h>
#include <skalibs/strerr2.h>
#include <skalibs/env.h>
#include <skalibs/exec.h>
#define dienomem() strerr_diefu1sys(111, "stralloc_catb")
// macros from outside
/* const char* EXECLINEB_PATH; */
/* const char* EXECLINE_BIN_PATH; */
int main(int argc, char const* argv[], char const *const *envp)
{
PROG = "execlineb-wrapper";
char const* path = getenv("PATH");
stralloc path_modif = STRALLOC_ZERO;
// modify PATH if unset or EXECLINEB_BIN_PATH is not yet there
if ( !path || ! strstr(path, EXECLINE_BIN_PATH())) {
// prepend our execline path
if ( ! stralloc_cats(&path_modif, "PATH=")
|| ! stralloc_cats(&path_modif, EXECLINE_BIN_PATH()) ) dienomem();
// old path was not empty
if ( path && path[0] ) {
if ( ! stralloc_catb(&path_modif, ":", 1)
|| ! stralloc_cats(&path_modif, path) ) dienomem();
}
// append final \0
if ( ! stralloc_0(&path_modif) ) dienomem();
}
// exec into execlineb and append path_modif to the environment
xmexec_aem(
EXECLINEB_PATH(),
argv,
envp,
path_modif.s, path_modif.len
);
}