const char *S_pathname_impl(const char *inpath, char *buffer) {
if (*inpath != '~') { return inpath; }
else {
#define setp(c) if (p > buffer + PATH_MAX) return NULL; else *p++ = (c)
static char path[PATH_MAX];
char *p;
const char *ip, *dir;
if (buffer == NULL) buffer = path;
ip = inpath + 1;
if (*ip == 0 || DIRMARKERP(*ip)) {
if (!(dir = S_homedir())) return NULL;
} else {
#ifdef WIN32
return inpath;
#else
struct passwd *pwent;
p = buffer;
while (*ip != 0 && !DIRMARKERP(*ip)) setp(*ip++);
setp(0);
if (!(pwent = getpwnam(buffer)) || !(dir = pwent->pw_dir))
return NULL;
#endif /* WIN32 */
}
p = buffer;
while (*dir != 0) setp(*dir++);
while (*ip != 0) setp(*ip++);
setp(0);
return buffer;
#undef setp
}
}
/* raises an exception if insufficient space cannot be malloc'd.
otherwise returns a freshly allocated version of inpath with ~ (home directory)
prefix expanded, if possible */
char *S_malloc_pathname(const char *inpath) {
char *outpath;
const char *ip;
#ifdef WIN32
if (*inpath == '~' && (*(ip = inpath + 1) == 0 || DIRMARKERP(*ip))) {
const char *homedrive, *homepath;
size_t n1, n2, n3;
if ((homedrive = getenv("HOMEDRIVE")) != NULL && (homepath = getenv("HOMEPATH")) != NULL) {
n1 = strlen(homedrive);
n2 = strlen(homepath);
n3 = strlen(ip) + 1;
if ((outpath = malloc(n1 + n2 + n3)) == NULL) S_error("expand_pathname", "malloc failed");
memcpy(outpath, homedrive, n1);
memcpy(outpath + n1, homepath, n2);
memcpy(outpath + n1 + n2, ip, n3);
return outpath;
}
}
#else /* WIN32 */
if (*inpath == '~') {
const char *dir;
size_t n1, n2;
struct passwd *pwent;
if (*(ip = inpath + 1) == 0 || DIRMARKERP(*ip)) {
if ((dir = getenv("HOME")) == NULL)
if ((pwent = getpwuid(getuid())) != NULL)
dir = pwent->pw_dir;
} else {
char *userbuf;
const char *user_start = ip;
do {
ip += 1;
}
while (*ip != 0 && !DIRMARKERP(*ip));
if ((userbuf = malloc(ip - user_start + 1)) == NULL) S_error("expand_pathname", "malloc failed");
memcpy(userbuf, user_start, ip - user_start);
userbuf[ip - user_start] = 0;
dir = (pwent = getpwnam(userbuf)) != NULL ? pwent->pw_dir : NULL;
free(userbuf);
}
if (dir != NULL) {
n1 = strlen(dir);
n2 = strlen(ip) + 1;
if ((outpath = malloc(n1 + n2)) == NULL) S_error("expand_pathname", "malloc failed");
memcpy(outpath, dir, n1);
memcpy(outpath + n1, ip, n2);
return outpath;
}
}
#endif /* WIN32 */
/* if no ~ or tilde dir can't be found, copy inpath */
{
size_t n = strlen(inpath) + 1;
outpath = (char *)malloc(n);
memcpy(outpath, inpath, n);
return outpath;
}
}
