source: azure_iot_hub/trunk/musl-1.1.18/src/misc/setrlimit.c@ 388

#include <sys/resource.h>
#include <errno.h>
#include "syscall.h"
#include "libc.h"

#define MIN(a, b) ((a)<(b) ? (a) : (b))
#define FIX(x) do{ if ((x)>=SYSCALL_RLIM_INFINITY) (x)=RLIM_INFINITY; }while(0)

int __setrlimit(int resource, const struct rlimit *rlim)
{
        unsigned long k_rlim[2];
        struct rlimit tmp;
        if (SYSCALL_RLIM_INFINITY != RLIM_INFINITY) {
                tmp = *rlim;
                FIX(tmp.rlim_cur);
                FIX(tmp.rlim_max);
                rlim = &tmp;
        }
        int ret = __syscall(SYS_prlimit64, 0, resource, rlim, 0);
        if (ret != -ENOSYS) return ret;
        k_rlim[0] = MIN(rlim->rlim_cur, MIN(-1UL, SYSCALL_RLIM_INFINITY));
        k_rlim[1] = MIN(rlim->rlim_max, MIN(-1UL, SYSCALL_RLIM_INFINITY));
        return __syscall(SYS_setrlimit, resource, k_rlim);
}

struct ctx {
        const struct rlimit *rlim;
        int res;
        int err;
};

static void do_setrlimit(void *p)
{
        struct ctx *c = p;
        if (c->err>0) return;
        c->err = -__setrlimit(c->res, c->rlim);
}

int setrlimit(int resource, const struct rlimit *rlim)
{
        struct ctx c = { .res = resource, .rlim = rlim, .err = -1 };
        __synccall(do_setrlimit, &c);
        if (c.err) {
                if (c.err>0) errno = c.err;
                return -1;
        }
        return 0;
}

LFS64(setrlimit);