386BSD 0.1 development

Work on file usr/src/usr.bin/rcs/src/curdir.c

Co-Authored-By: Lynne Greer Jolitz <ljolitz@cardio.ucsf.edu>
Synthesized-from: 386BSD-0.1

diff --git a/usr/src/usr.bin/rcs/src/curdir.c b/usr/src/usr.bin/rcs/src/curdir.c
new file mode 100644 (file)
index 0000000..f100919
--- /dev/null
+++ b/usr/src/usr.bin/rcs/src/curdir.c
@@ -0,0 +1,142 @@
+/* Copyright (C) 1982, 1988, 1989 Walter Tichy
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by Walter Tichy.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Report all problems and direct all questions to:
+ *   rcs-bugs@cs.purdue.edu
+ * 
+
+
+
+
+
+
+
+*/
+
+/*******************************************************************
+ *                     curdir: get current directory
+ *******************************************************************
+ * returns full pathname of working (current) directory.
+ * This is an adaptation of pwd, and works for grafted directories.
+ * Unlike pwd, returns to current directory after it is finished.
+ * Uses stdio buffering for directory reads.
+ */
+
+ static char rcsid[]=
+ "$Header: /usr/src/local/bin/rcs/src/RCS/curdir.c,v 3.3 89/05/01 15:11:49 narten Exp $";
+
+/*******************************************************************
+ *      $Log:  curdir.c,v $
+ * Revision 3.3  89/05/01  15:11:49  narten
+ * changed copyright header to reflect current distribution rules
+ * 
+ * Revision 3.2  87/10/18  10:21:49  narten
+ * Updating version numbers. Changes relative to 1.1 are actually 
+ * relative to 3.2
+ * 
+ * Revision 1.1  84/01/23  14:50:01  kcs
+ * Initial revision
+ * 
+ * Revision 3.2  82/12/24  15:41:51  wft
+ * Changed curdir() such that it returns a pointer to the pathname of
+ * the current working directory, just as Berkeley's getcwd().
+ * 
+ * Revision 3.1  82/10/18  21:16:21  wft
+ * curdir() now uses stdio buffering for directory reads,
+ * returns to working directory after done, and closes the directories.
+ * A testprogram was also added.
+ * 
+ *******************************************************************/
+ 
+
+#include        "rcsbase.h"
+#include        <sys/param.h>
+#include        <sys/stat.h>
+#include        <sys/dir.h>
+#define dot     "."
+#define dotdot  ".."
+
+
+static char cwd[NCPPN];
+
+char * curdir()
+/* Function: places the pathname of the current directory into cwd
+ * and returns a pointer to it. Returns NULL on failure.
+ */
+{
+        FILE    *file;
+        struct  stat    d, dd;
+        struct  direct  dir;
+
+        int rdev, rino;
+        int off;
+        register i,j;
+
+        cwd[off= 0] = '/';
+        cwd[1] = '\0';
+        stat("/", &d);
+        rdev = d.st_dev;
+        rino = d.st_ino;
+        for (;;) {
+                if (stat(dot, &d)<0) return NULL;
+                if (d.st_ino==rino && d.st_dev==rdev) {
+                        if (cwd[off] == '/') cwd[off] = '\0';
+                        chdir(cwd); /*change back to current directory*/
+                        return cwd;
+                }
+                if ((file = fopen(dotdot,"r")) == NULL) return NULL;
+                if (fstat(fileno(file), &dd)<0) goto fail;
+                chdir(dotdot);
+                if(d.st_dev == dd.st_dev) {
+                        if(d.st_ino == dd.st_ino) {
+                            if (cwd[off] == '/') cwd[off] = '\0';
+                            chdir(cwd); /*change back to current directory*/
+                            fclose(file);
+                            return cwd;
+                        }
+                        do {
+                            if (fread((char *)&dir, sizeof(dir), 1, file) !=1)
+                                goto fail;
+                        } while (dir.d_ino != d.st_ino);
+                }
+                else do {
+                        if(fread((char *)&dir, sizeof(dir), 1, file) != 1) {
+                            goto fail;
+                        }
+                        stat(dir.d_name, &dd);
+                } while(dd.st_ino != d.st_ino || dd.st_dev != d.st_dev);
+                fclose(file);
+
+                /* concatenate file name */
+                i = -1;
+                while (dir.d_name[++i] != 0);
+                for(j=off+1; j>0; --j)
+                        cwd[j+i+1] = cwd[j];
+                off=i+off+1;
+                cwd[i+1] = '/';
+                for(--i; i>=0; --i)
+                        cwd[i+1] = dir.d_name[i];
+        } /* end for */
+
+fail:   fclose(file);
+        return NULL;
+}
+
+
+#ifdef TEST
+main ()
+{
+        printf ("pwd = %s\n", curdir());
+}
+#endif TEST
+