Add in a bunch of junk. Busybox now compiles (except for mkfs.minix and

fsck.minix).  Of course, it doesn't link yet due to missing functions, but
hey...  At least it is now easy to see what isn't working. :-)
 -Erik

1 files changed, 168 insertions, 0 deletions

diff --git a/libc/stdlib/realpath.c b/libc/stdlib/realpath.c
new file mode 100644
index 000000000..d053cfcaf
--- /dev/null
+++ b/libc/stdlib/realpath.c
@@ -0,0 +1,168 @@
+/*
+ * realpath.c -- canonicalize pathname by removing symlinks
+ * Copyright (C) 1993 Rick Sladkey <jrs@world.std.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library Public License for more details.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+#include <limits.h>			/* for PATH_MAX */
+#include <sys/param.h>			/* for MAXPATHLEN */
+#include <errno.h>
+
+#include <sys/stat.h>			/* for S_IFLNK */
+
+#ifndef PATH_MAX
+#ifdef _POSIX_VERSION
+#define PATH_MAX _POSIX_PATH_MAX
+#else
+#ifdef MAXPATHLEN
+#define PATH_MAX MAXPATHLEN
+#else
+#define PATH_MAX 1024
+#endif
+#endif
+#endif
+
+#define MAX_READLINKS 32
+
+#ifdef __STDC__
+char *realpath(const char *path, char resolved_path [])
+#else
+char *realpath(path, resolved_path)
+const char *path;
+char resolved_path [];
+#endif
+{
+	char copy_path[PATH_MAX];
+	char link_path[PATH_MAX];
+	char got_path [PATH_MAX];
+	char *new_path = got_path;
+	char *max_path;
+	int readlinks = 0;
+	int n;
+
+	/* Make a copy of the source path since we may need to modify it. */
+	if (strlen(path)>=PATH_MAX-2) {
+		errno = ENAMETOOLONG;
+		return NULL;
+	}
+	strcpy(copy_path, path);
+	path = copy_path;
+	max_path = copy_path + PATH_MAX - 2;
+	/* If it's a relative pathname use getwd for starters. */
+	if (*path != '/') {
+		/* Ohoo... */
+#define HAVE_GETCWD
+#ifdef HAVE_GETCWD
+		getcwd(new_path, PATH_MAX - 1);
+#else
+		getwd(new_path);
+#endif
+		new_path += strlen(new_path);
+		if (new_path[-1] != '/')
+			*new_path++ = '/';
+	}
+	else {
+		*new_path++ = '/';
+		path++;
+	}
+	/* Expand each slash-separated pathname component. */
+	while (*path != '\0') {
+		/* Ignore stray "/". */
+		if (*path == '/') {
+			path++;
+			continue;
+		}
+		if (*path == '.') {
+			/* Ignore ".". */
+			if (path[1] == '\0' || path[1] == '/') {
+				path++;
+				continue;
+			}
+			if (path[1] == '.') {
+				if (path[2] == '\0' || path[2] == '/') {
+					path += 2;
+					/* Ignore ".." at root. */
+					if (new_path == got_path + 1)
+						continue;
+					/* Handle ".." by backing up. */
+					while ((--new_path)[-1] != '/')
+						;
+					continue;
+				}
+			}
+		}
+		/* Safely copy the next pathname component. */
+		while (*path != '\0' && *path != '/') {
+			if (path > max_path) {
+				errno = ENAMETOOLONG;
+				return NULL;
+			}
+			*new_path++ = *path++;
+		}
+#ifdef S_IFLNK
+		/* Protect against infinite loops. */
+		if (readlinks++ > MAX_READLINKS) {
+			errno = ELOOP;
+			return NULL;
+		}
+		/* See if latest pathname component is a symlink. */
+		*new_path = '\0';
+		n = readlink(got_path, link_path, PATH_MAX - 1);
+		if (n < 0) {
+			/* EINVAL means the file exists but isn't a symlink. */
+			if (errno != EINVAL) {
+				/* Make sure it's null terminated. */
+				*new_path = '\0';
+				strcpy (resolved_path, got_path);
+				return NULL;
+			}
+		}
+		else {
+			/* Note: readlink doesn't add the null byte. */
+			link_path[n] = '\0';
+			if (*link_path == '/')
+				/* Start over for an absolute symlink. */
+				new_path = got_path;
+			else
+				/* Otherwise back up over this component. */
+				while (*(--new_path) != '/')
+					;
+			/* Safe sex check. */
+			if (strlen(path) + n >= PATH_MAX-2) {
+				errno = ENAMETOOLONG;
+				return NULL;
+			}
+			/* Insert symlink contents into path. */
+			strcat(link_path, path);
+			strcpy(copy_path, link_path);
+			path = copy_path;
+		}
+#endif /* S_IFLNK */
+		*new_path++ = '/';
+	}
+	/* Delete trailing slash but don't whomp a lone slash. */
+	if (new_path != got_path + 1 && new_path[-1] == '/')
+		new_path--;
+	/* Make sure it's null terminated. */
+	*new_path = '\0';
+	strcpy (resolved_path, got_path);
+	return resolved_path;
+}