0.6.12.49:

[sbcl.git] / src / runtime / wrap.c

diff --git a/src/runtime/wrap.c b/src/runtime/wrap.c
index 3f205a1..9a45b23 100644 (file)
--- a/src/runtime/wrap.c
+++ b/src/runtime/wrap.c
@@ -29,6 +29,8 @@
 #include <string.h>
 #include <unistd.h>
 
+#include "runtime.h"
+#include "sbcl.h"
 #include "util.h"
 \f   
 /*
@@ -104,32 +106,79 @@ free_directory_lispy_filenames(char** directory_lispy_filenames)
 }
 \f
 /*
+ * readlink(2) stuff
+ */
+
+/* a wrapped version of readlink(2):
+ *   -- If path isn't a symlink, or is a broken symlink, return 0.
+ *   -- If path is a symlink, return a newly allocated string holding
+ *      the thing it's linked to.
+ */
+char *
+wrapped_readlink(char *path)
+{
+    int strlen_path = strlen(path);
+    int bufsiz = strlen(path) + 16;
+    while (1) {
+       char *result = malloc(bufsiz);
+       int n_read = readlink(path, result, n_read);
+       if (n_read < 0) {
+           return 0;
+       } else if (n_read < bufsiz) {
+           result[n_read] = 0;
+           return result;
+       } else {
+           free(result);
+           bufsiz *= 2;
+       }
+    }
+}
+\f
+/*
  * stat(2) stuff
  */
 
-typedef long my_dev_t;
+/* As of 0.6.12, the FFI can't handle 64-bit values. For now, we use
+ * these munged-to-32-bits values for might-be-64-bit slots of
+ * stat_wrapper as a workaround, so that at least we can still work
+ * when values are small.
+ *
+ * FIXME: But of course we should fix the FFI so that we can use the
+ * actual 64-bit values instead. */
+typedef long ffi_dev_t; /* since Linux dev_t can be 64 bits */
+typedef u32 ffi_off_t; /* since OpenBSD 2.8 st_size is 64 bits */
 
 /* a representation of stat(2) results which doesn't depend on CPU or OS */
 struct stat_wrapper {
-    my_dev_t      st_dev;         /* device */
-    ino_t         st_ino;         /* inode */
-    mode_t        st_mode;        /* protection */
-    nlink_t       st_nlink;       /* number of hard links */
-    uid_t         st_uid;         /* user ID of owner */
-    gid_t         st_gid;         /* group ID of owner */
-    my_dev_t      st_rdev;        /* device type (if inode device) */
-    off_t         st_size;        /* total size, in bytes */
-    unsigned long st_blksize;     /* blocksize for filesystem I/O */
-    unsigned long st_blocks;      /* number of blocks allocated */
-    time_t        st_atime;       /* time of last access */
-    time_t        st_mtime;       /* time of last modification */
-    time_t        st_ctime;       /* time of last change */
+    /* KLUDGE: The verbose wrapped_st_ prefixes are to protect us from
+     * the C preprocessor as wielded by the fiends of OpenBSD, who do
+     * things like
+     *    #define st_atime        st_atimespec.tv_sec
+     * I remember when I was young and innocent, I read about how the
+     * C preprocessor isn't to be used to globally munge random
+     * lowercase symbols like this, because things like this could
+     * happen, and I nodded sagely. But now I know better.:-| This is
+     * another entry for Dan Barlow's ongoing episodic rant about C
+     * header files, I guess.. -- WHN 2001-05-10 */
+    ffi_dev_t     wrapped_st_dev;         /* device */
+    ino_t         wrapped_st_ino;         /* inode */
+    mode_t        wrapped_st_mode;        /* protection */
+    nlink_t       wrapped_st_nlink;       /* number of hard links */
+    uid_t         wrapped_st_uid;         /* user ID of owner */
+    gid_t         wrapped_st_gid;         /* group ID of owner */
+    ffi_dev_t     wrapped_st_rdev;        /* device type (if inode device) */
+    ffi_off_t     wrapped_st_size;        /* total size, in bytes */
+    unsigned long wrapped_st_blksize;     /* blocksize for filesystem I/O */
+    unsigned long wrapped_st_blocks;      /* number of blocks allocated */
+    time_t        wrapped_st_atime;       /* time_t of last access */
+    time_t        wrapped_st_mtime;       /* time_t of last modification */
+    time_t        wrapped_st_ctime;       /* time_t of last change */
 };
 
 static void 
 copy_to_stat_wrapper(struct stat_wrapper *to, struct stat *from)
 {
-#define FROB(stem) to->st_##stem = from->st_##stem
+#define FROB(stem) to->wrapped_st_##stem = from->st_##stem
     FROB(dev);
     FROB(ino);
     FROB(mode);