2 * wrappers around low-level operations to provide a simpler interface
3 * to the operations that Lisp needs
5 * The functions in this file are typically called directly from Lisp.
6 * Thus, when their signature changes, they don't need updates in a .h
7 * file somewhere, but they do need updates in the Lisp code. FIXME:
8 * It would be nice to enforce this at compile time. It mighn't even
9 * be all that hard: make the cross-compiler versions of DEFINE-ALIEN-FOO
10 * macros accumulate strings in a list which then gets written out at
11 * the end of sbcl2.h at the end of cross-compilation, then rerun
12 * 'make' in src/runtime/ using the new sbcl2.h as sbcl.h (and make
13 * sure that all the files in src/runtime/ include sbcl.h). */
16 * This software is part of the SBCL system. See the README file for
19 * This software is derived from the CMU CL system, which was
20 * written at Carnegie Mellon University and released into the
21 * public domain. The software is in the public domain and is
22 * provided with absolutely no warranty. See the COPYING and CREDITS
23 * files for more information.
26 #include <sys/types.h>
38 /* KLUDGE: Neither the OpenBSD nor the Linux man page give a header
39 * file to find this in (?). -- WHN 2002-02-07 */
40 extern char **environ;
43 * stuff needed by CL:DIRECTORY and other Lisp directory operations
46 /* Unix directory operations think of "." and ".." as filenames, but
47 * Lisp directory operations do not. */
49 is_lispy_filename(const char *filename)
51 return strcmp(filename, ".") && strcmp(filename, "..");
54 /* Return a zero-terminated array of strings holding the Lispy filenames
55 * (i.e. excluding the Unix magic "." and "..") in the named directory. */
57 alloc_directory_lispy_filenames(const char *directory_name)
59 DIR *dir_ptr = opendir(directory_name);
62 if (dir_ptr) { /* if opendir success */
66 if (0 == voidacc_ctor(&va)) { /* if voidacc_ctor success */
67 struct dirent *dirent_ptr;
69 while ( (dirent_ptr = readdir(dir_ptr)) ) { /* until end of data */
70 char* original_name = dirent_ptr->d_name;
71 if (is_lispy_filename(original_name)) {
72 /* strdup(3) is in Linux and *BSD. If you port
73 * somewhere else that doesn't have it, it's easy
75 char* dup_name = strdup(original_name);
76 if (!dup_name) { /* if strdup failure */
79 if (voidacc_acc(&va, dup_name)) { /* if acc failure */
84 result = (char**)voidacc_give_away_result(&va);
89 /* ignoring closedir(3) return code, since what could we do?
91 * "Never ask questions you don't want to know the answer to."
92 * -- William Irving Zumwalt (Rich Cook, _The Wizardry Quested_) */
99 /* Free a result returned by alloc_directory_lispy_filenames(). */
101 free_directory_lispy_filenames(char** directory_lispy_filenames)
105 /* Free the strings. */
106 for (p = directory_lispy_filenames; *p; ++p) {
110 /* Free the table of strings. */
111 free(directory_lispy_filenames);
118 /* a wrapped version of readlink(2):
119 * -- If path isn't a symlink, or is a broken symlink, return 0.
120 * -- If path is a symlink, return a newly allocated string holding
121 * the thing it's linked to. */
123 wrapped_readlink(char *path)
125 int bufsiz = strlen(path) + 16;
127 char *result = malloc(bufsiz);
128 int n_read = readlink(path, result, bufsiz);
132 } else if (n_read < bufsiz) {
146 /* As of 0.6.12, the FFI can't handle 64-bit values. For now, we use
147 * these munged-to-32-bits values for might-be-64-bit slots of
148 * stat_wrapper as a workaround, so that at least we can still work
149 * when values are small.
151 * FIXME: But of course we should fix the FFI so that we can use the
152 * actual 64-bit values instead. */
153 typedef long ffi_dev_t; /* since Linux dev_t can be 64 bits */
154 typedef u32 ffi_off_t; /* since OpenBSD 2.8 st_size is 64 bits */
156 /* a representation of stat(2) results which doesn't depend on CPU or OS */
157 struct stat_wrapper {
158 /* KLUDGE: The verbose wrapped_st_ prefixes are to protect us from
159 * the C preprocessor as wielded by the fiends of OpenBSD, who do
161 * #define st_atime st_atimespec.tv_sec
162 * I remember when I was young and innocent, I read about how the
163 * C preprocessor isn't to be used to globally munge random
164 * lowercase symbols like this, because things like this could
165 * happen, and I nodded sagely. But now I know better.:-| This is
166 * another entry for Dan Barlow's ongoing episodic rant about C
167 * header files, I guess.. -- WHN 2001-05-10 */
168 ffi_dev_t wrapped_st_dev; /* device */
169 ino_t wrapped_st_ino; /* inode */
170 mode_t wrapped_st_mode; /* protection */
171 nlink_t wrapped_st_nlink; /* number of hard links */
172 uid_t wrapped_st_uid; /* user ID of owner */
173 gid_t wrapped_st_gid; /* group ID of owner */
174 ffi_dev_t wrapped_st_rdev; /* device type (if inode device) */
175 ffi_off_t wrapped_st_size; /* total size, in bytes */
176 unsigned long wrapped_st_blksize; /* blocksize for filesystem I/O */
177 unsigned long wrapped_st_blocks; /* number of blocks allocated */
178 time_t wrapped_st_atime; /* time_t of last access */
179 time_t wrapped_st_mtime; /* time_t of last modification */
180 time_t wrapped_st_ctime; /* time_t of last change */
184 copy_to_stat_wrapper(struct stat_wrapper *to, struct stat *from)
186 #define FROB(stem) to->wrapped_st_##stem = from->st_##stem
204 stat_wrapper(const char *file_name, struct stat_wrapper *buf)
206 struct stat real_buf;
208 if ((ret = stat(file_name,&real_buf)) >= 0)
209 copy_to_stat_wrapper(buf, &real_buf);
214 lstat_wrapper(const char *file_name, struct stat_wrapper *buf)
216 struct stat real_buf;
218 if ((ret = lstat(file_name,&real_buf)) >= 0)
219 copy_to_stat_wrapper(buf, &real_buf);
224 fstat_wrapper(int filedes, struct stat_wrapper *buf)
226 struct stat real_buf;
228 if ((ret = fstat(filedes,&real_buf)) >= 0)
229 copy_to_stat_wrapper(buf, &real_buf);
237 /* Return a newly-allocated string holding the username for "uid", or
238 * NULL if there's no such user.
240 * KLUDGE: We also return NULL if malloc() runs out of memory
241 * (returning strdup() result) since it's not clear how to handle that
242 * error better. -- WHN 2001-12-28 */
244 uid_username(int uid)
246 struct passwd *p = getpwuid(uid);
248 /* The object *p is a static struct which'll be overwritten by
249 * the next call to getpwuid(), so it'd be unsafe to return
250 * p->pw_name without copying. */
251 return strdup(p->pw_name);
258 * functions to get miscellaneous C-level variables
260 * (Doing this by calling functions lets us borrow the smarts of the C
261 * linker, so that things don't blow up when libc versions and thus
262 * variable locations change between compile time and run time.)