pathconf can't use fpathconf or it will block opening FIFOs

diff --git a/libc/unistd/pathconf.c b/libc/unistd/pathconf.c
index 64ed795..d7fa99f 100644 (file)
--- a/libc/unistd/pathconf.c
+++ b/libc/unistd/pathconf.c
@@ -17,32 +17,234 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+
+/* It would be great it this could be implemented using fpathconf,
+ * but that doesn't work out very well (think FIFOs and sockets) */
+
 #include <errno.h>
 #include <unistd.h>
 #include <limits.h>
+#include <sys/statfs.h>
 #include <errno.h>
 #include <stddef.h>
 #include <unistd.h>
 #include <limits.h>
 #include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/statfs.h>
+//#include <sys/statvfs.h>
+
+//#include "linux_fsinfo.h"
+
+
+/* The Linux kernel headers mention this as a kind of generic value.  */
+#define LINUX_LINK_MAX 127
 
 
 /* Get file-specific information about descriptor FD.  */
 long int pathconf(const char *path, int name)
 {
-    int fd;
-
     if (path[0] == '\0')
     {
        __set_errno (ENOENT);
        return -1;
     }
 
-    fd = open(path, O_RDONLY); 
-    if (fd < 0) {
-       __set_errno (ENOENT);
-       return -1;
+    if (name == _PC_LINK_MAX)
+    {
+       /* Cut some corners */
+#if 0
+       struct statfs fsbuf;
+
+       /* Determine the filesystem type.  */
+       if (statfs (path, &fsbuf) < 0)
+       {
+           if (errno == ENOSYS)
+               /* not possible, return the default value.  */
+               return LINUX_LINK_MAX;
+
+           /* Some error occured.  */
+           return -1;
+       }
+
+       switch (fsbuf.f_type)
+       {
+           case EXT2_SUPER_MAGIC:
+               return EXT2_LINK_MAX;
+
+           case MINIX_SUPER_MAGIC:
+           case MINIX_SUPER_MAGIC2:
+               return MINIX_LINK_MAX;
+
+           case MINIX2_SUPER_MAGIC:
+           case MINIX2_SUPER_MAGIC2:
+               return MINIX2_LINK_MAX;
+
+           case XENIX_SUPER_MAGIC:
+               return XENIX_LINK_MAX;
+
+           case SYSV4_SUPER_MAGIC:
+           case SYSV2_SUPER_MAGIC:
+               return SYSV_LINK_MAX;
+
+           case COH_SUPER_MAGIC:
+               return COH_LINK_MAX;
+
+           case UFS_MAGIC:
+           case UFS_CIGAM:
+               return UFS_LINK_MAX;
+
+           case REISERFS_SUPER_MAGIC:
+               return REISERFS_LINK_MAX;
+
+           default:
+               return LINUX_LINK_MAX;
+       }
+#else
+       return LINUX_LINK_MAX;
+#endif
     }
-    return (fpathconf(fd, name));
+
+    switch (name)
+    {
+       default:
+           __set_errno (EINVAL);
+           return -1;
+
+       case _PC_MAX_CANON:
+#ifdef MAX_CANON
+           return MAX_CANON;
+#else
+           return -1;
+#endif
+
+       case _PC_MAX_INPUT:
+#ifdef MAX_INPUT
+           return MAX_INPUT;
+#else
+           return -1;
+#endif
+
+       case _PC_NAME_MAX:
+#ifdef NAME_MAX
+           {
+               struct statfs buf;
+               int save_errno = errno;
+
+               if (statfs (path, &buf) < 0)
+               {
+                   if (errno == ENOSYS)
+                   {
+                       errno = save_errno;
+                       return NAME_MAX;
+                   }
+                   return -1;
+               }
+               else
+               {
+#ifdef _STATFS_F_NAMELEN
+                   return buf.f_namelen;
+#else
+# ifdef _STATFS_F_NAME_MAX
+                   return buf.f_name_max;
+# else
+                   return NAME_MAX;
+# endif
+#endif
+               }
+           }
+#else
+           return -1;
+#endif
+
+       case _PC_PATH_MAX:
+#ifdef PATH_MAX
+           return PATH_MAX;
+#else
+           return -1;
+#endif
+
+       case _PC_PIPE_BUF:
+#ifdef PIPE_BUF
+           return PIPE_BUF;
+#else
+           return -1;
+#endif
+
+       case _PC_CHOWN_RESTRICTED:
+#ifdef _POSIX_CHOWN_RESTRICTED
+           return _POSIX_CHOWN_RESTRICTED;
+#else
+           return -1;
+#endif
+
+       case _PC_NO_TRUNC:
+#ifdef _POSIX_NO_TRUNC
+           return _POSIX_NO_TRUNC;
+#else
+           return -1;
+#endif
+
+       case _PC_VDISABLE:
+#ifdef _POSIX_VDISABLE
+           return _POSIX_VDISABLE;
+#else
+           return -1;
+#endif
+
+       case _PC_SYNC_IO:
+#ifdef _POSIX_SYNC_IO
+           return _POSIX_SYNC_IO;
+#else
+           return -1;
+#endif
+
+       case _PC_ASYNC_IO:
+#if defined _POSIX_ASYNC_IO && defined __UCLIBC_HAVE_LFS__ 
+           {
+               /* AIO is only allowed on regular files and block devices.  */
+               struct stat st;
+
+               if (stat (path, &st) < 0 || (! S_ISREG (st.st_mode) && ! S_ISBLK (st.st_mode)))
+                   return -1;
+               else
+                   return 1;
+           }
+#else
+           return -1;
+#endif
+
+       case _PC_PRIO_IO:
+#ifdef _POSIX_PRIO_IO
+           return _POSIX_PRIO_IO;
+#else
+           return -1;
+#endif
+
+       case _PC_SOCK_MAXBUF:
+#ifdef SOCK_MAXBUF
+           return SOCK_MAXBUF;
+#else
+           return -1;
+#endif
+
+       case _PC_FILESIZEBITS:
+#ifdef FILESIZEBITS
+           return FILESIZEBITS;
+#else
+           /* We let platforms with larger file sizes overwrite this value.  */
+           return 32;
+#endif
+
+           /* Be lazy -- skip these */
+       case _PC_REC_INCR_XFER_SIZE:
+       case _PC_REC_MAX_XFER_SIZE:
+       case _PC_REC_MIN_XFER_SIZE:
+       case _PC_REC_XFER_ALIGN:
+       case _PC_ALLOC_SIZE_MIN:
+       case _PC_SYMLINK_MAX:
+           return -1;
+    }
+
 }