source: azure_iot_hub/trunk/musl-1.1.18/src/passwd/getpw_r.c@ 389

#include "pwf.h"
#include <pthread.h>

#define FIX(x) (pw->pw_##x = pw->pw_##x-line+buf)

static int getpw_r(const char *name, uid_t uid, struct passwd *pw, char *buf, size_t size, struct passwd **res)
{
        char *line = 0;
        size_t len = 0;
        int rv = 0;
        int cs;

        pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);

        rv = __getpw_a(name, uid, pw, &line, &len, res);
        if (*res && size < len) {
                *res = 0;
                rv = ERANGE;
        }
        if (*res) {
                memcpy(buf, line, len);
                FIX(name);
                FIX(passwd);
                FIX(gecos);
                FIX(dir);
                FIX(shell);
        }
        free(line);
        pthread_setcancelstate(cs, 0);
        if (rv) errno = rv;
        return rv;
}

int getpwnam_r(const char *name, struct passwd *pw, char *buf, size_t size, struct passwd **res)
{
        return getpw_r(name, 0, pw, buf, size, res);
}

int getpwuid_r(uid_t uid, struct passwd *pw, char *buf, size_t size, struct passwd **res)
{
        return getpw_r(0, uid, pw, buf, size, res);
}