5 /* Originally written in Perl by John Bazik; rewritten in C by Ben Sugars.
6 * Comments from the orignal:
7 * This is a faster version of getcwd. It's also more dangerous
8 * because you might chdir out of a directory that you can't chdir
13 /* XXX Should we just use getcwd(3) if available? */
15 int orig_cdev, orig_cino, cdev, cino, odev, oino, tdev, tino;
16 int i = 0, j = 0, k = 0, ndirs = 16, pathlen = 0, namelen;
21 Newz(0, names, ndirs, char*);
23 if (PerlLIO_lstat(".", &statbuf) < 0) {
27 orig_cdev = statbuf.st_dev;
28 orig_cino = statbuf.st_ino;
35 if (PerlDir_chdir("..") < 0) {
39 if (PerlLIO_stat(".", &statbuf) < 0) {
43 cdev = statbuf.st_dev;
44 cino = statbuf.st_ino;
45 if (odev == cdev && oino == cino)
48 if (!(dir = PerlDir_open("."))) {
53 while ((dp = PerlDir_read(dir)) != NULL) {
54 if (PerlLIO_lstat(dp->d_name, &statbuf) < 0) {
58 if (strEQ(dp->d_name, "."))
60 if (strEQ(dp->d_name, ".."))
62 tdev = statbuf.st_dev;
63 tino = statbuf.st_ino;
64 if (tino == oino && tdev == odev)
75 Renew(names, ndirs, char*);
78 namelen = dp->d_namlen;
80 namelen = strlen(dp->d_name);
82 Newz(0, *(names + i), namelen + 1, char);
83 Copy(dp->d_name, *(names + i), namelen, char);
84 *(names[i] + namelen) = '\0';
85 pathlen += (namelen + 1);
91 if (PerlDir_close(dir) < 0) {
98 Newz(0, path, pathlen + 1, char);
99 for (j = i - 1; j >= 0; j--) {
101 Copy(names[j], path + k + 1, strlen(names[j]) + 1, char);
102 k = k + strlen(names[j]) + 1;
106 if (PerlDir_chdir(path) < 0) {
111 if (PerlLIO_stat(".", &statbuf) < 0) {
116 cdev = statbuf.st_dev;
117 cino = statbuf.st_ino;
118 if (cdev != orig_cdev || cino != orig_cino)
119 Perl_croak(aTHX_ "Unstable directory path, current directory changed unexpectedly");
126 _cwdxs_abs_path(char *start)
130 char dotdots[MAXPATHLEN] = { 0 };
131 char name[MAXPATHLEN] = { 0 };
134 struct stat cst, pst, tst;
136 if (PerlLIO_stat(start, &cst) < 0) {
137 warn("abs_path: stat(\"%s\"): %s", start, Strerror(errno));
141 Newz(0, cwd, MAXPATHLEN, char);
142 Copy(start, dotdots, strlen(start), char);
145 strcat(dotdots, "/..");
146 StructCopy(&cst, &pst, struct stat);
148 if (PerlLIO_stat(dotdots, &cst) < 0) {
150 warn("abs_path: stat(\"%s\"): %s", dotdots, Strerror(errno));
154 if (pst.st_dev == cst.st_dev && pst.st_ino == cst.st_ino) {
155 /* We've reached the root: previous is same as current */
158 STRLEN dotdotslen = strlen(dotdots);
160 /* Scan through the dir looking for name of previous */
161 if (!(parent = PerlDir_open(dotdots))) {
163 warn("abs_path: opendir(\"%s\"): %s", dotdots, Strerror(errno));
167 SETERRNO(0,SS$_NORMAL); /* for readdir() */
168 while ((dp = PerlDir_read(parent)) != NULL) {
169 if (strEQ(dp->d_name, "."))
171 if (strEQ(dp->d_name, ".."))
174 Copy(dotdots, name, dotdotslen, char);
175 name[dotdotslen] = '/';
177 namelen = dp->d_namlen;
179 namelen = strlen(dp->d_name);
181 Copy(dp->d_name, name + dotdotslen + 1, namelen, char);
182 name[dotdotslen + 1 + namelen] = 0;
184 if (PerlLIO_lstat(name, &tst) < 0) {
186 PerlDir_close(parent);
187 warn("abs_path: lstat(\"%s\"): %s", name, Strerror(errno));
191 if (tst.st_dev == pst.st_dev && tst.st_ino == pst.st_ino)
194 SETERRNO(0,SS$_NORMAL); /* for readdir() */
199 warn("abs_path: readdir(\"%s\"): %s", dotdots, Strerror(errno));
204 Move(cwd, cwd + namelen + 1, strlen(cwd), char);
205 Copy(dp->d_name, cwd + 1, namelen, char);
207 PerlDir_close(parent);
209 if (PerlDir_close(parent) < 0) {
210 warn("abs_path: closedir(\"%s\"): %s", dotdots, Strerror(errno));
223 MODULE = Cwd PACKAGE = Cwd
231 buf = _cwdxs_fastcwd();
233 PUSHs(sv_2mortal(newSVpv(buf, 0)));
240 _abs_path(start = ".")
245 buf = _cwdxs_abs_path(start);
247 PUSHs(sv_2mortal(newSVpv(buf, 0)));