CBS is a single-header library for writing build scripts in C. The philosophy behind this project is that the only tool you should ever need to build your C projects is a C compiler. Not Make, not Cmake, not Autoconf — just a C compiler.
Using C for your build system also has numerous advantages. C is portable to almost any platform, C is a turing-complete language that makes performing very specific build steps easy, and anyone working on your C project already knows C.
CBS does not aim to be the most powerful and ultimate high-level API. It simply aims to be a set of potentially useful functions and macros to make writing a build script in C a bit easier. If there is functionality you are missing, then add it. You’re a programmer aren’t you?
All functions and macros are documented in cbs.h.
CBS is very much inspired by Tsoding’s ‘Nob’.
Assuming you have a source file my-file.c — you can compile this build
script (called build.c for example) with cc build.c to bootstrap —
and then run ./a.out to build the my-file binary linked against the
liblux library.
If you make any modifications to the build script or to the cbs.h header, there is no need to manually recompile — the script will rebuild itself.
#include <stdlib.h>
#include "cbs.h"
#define CC "cc"
#define CFLAGS "-Wall", "-Wextra", "-Werror", "-O3"
#define TARGET "my-file"
int
main(int argc, char **argv)
{
int ec;
cmd_t cmd = {0};
struct strv v = {0};
cbsinit(argc, argv);
rebuild();
if (!foutdated(TARGET, TARGET ".c"))
return EXIT_SUCCESS;
cmdadd(&cmd, CC);
if (pcquery(&v, "liblux", PKGC_LIBS | PKGC_CFLAGS))
cmdaddv(&cmd, v.buf, v.len);
else
cmdadd(&cmd, "-llux");
cmdadd(&cmd, CFLAGS, "-o", TARGET, TARGET ".c");
cmdput(cmd);
if ((ec = cmdexec(cmd)) != EXIT_SUCCESS)
diex("%s failed with exit-code %d", *cmd._argv, ec);
return EXIT_SUCCESS;
}This is like the previous example, but you should compile with -lpthread. This is not the most efficient way to build a multi-file project, but this is simply for demonstration purposes.
#include <errno.h>
#include <string.h>
#define CBS_PTHREAD
#include "cbs.h"
#define CC "cc"
#define CFLAGS "-Wall", "-Wextra", "-Werror", "-O3"
#define TARGET "my-file"
static const char *sources[] = {"foo.c", "bar.c", "baz.c"};
static const char *objects[] = {"foo.o", "bar.o", "baz.o"};
static void build(void *);
int
main(int argc, char **argv)
{
int ec, cpus;
cmd_t cmd = {0};
tpool_t tp;
cbsinit(argc, argv);
rebuild();
if (!foutdatedv(TARGET, sources, lengthof(sources)))
return EXIT_SUCCESS;
if ((cpus = nproc()) == -1) {
if (errno)
die("nproc");
/* System not properly supported; default to 8 threads */
cpus = 8;
}
tpinit(&tp, cpus);
for (size_t i = 0; i < lengthof(sources); i++)
tpenq(&tp, build, sources[i], NULL);
tpwait(&tp);
tpfree(&tp);
cmdadd(&cmd, CC, "-o", TARGET);
cmdaddv(&cmd, objects, lengthof(objects));
cmdput(cmd);
if ((ec = cmdexec(cmd)) != EXIT_SUCCESS)
diex("%s failed with exit-code %d", *cmd._argv, ec);
return EXIT_SUCCESS;
}
void
build(void *arg)
{
int ec;
char *dst, *src = arg;
cmd_t cmd = {0};
for (size_t i = 0; i < lengthof(sources); i++) {
/* All the sources and objects have 3 letter names + an extension */
if (strncmp(src, objects[i], 3) == 0) {
dst = objects[i];
break;
}
}
cmdadd(&cmd, CC, CFLAGS, "-o", dst, "-c", src);
cmdput(cmd);
if ((ec = cmdexec(cmd)) != EXIT_SUCCESS)
diex("%s failed with exit-code %d", *cmd._argv, ec);
free(cmd._argv);
}