Support for more than one video directory

videodir.c

@@ -0,0 +1,182 @@
+/*
+ * videodir.c: Functions to maintain a distributed video directory
+ *
+ * See the main source file 'vdr.c' for copyright information and
+ * how to reach the author.
+ *
+ * $Id: videodir.c 1.1 2000/07/29 15:21:42 kls Exp $
+ */
+
+#include "videodir.h"
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include "tools.h"
+
+const char *VideoDirectory = "/video";
+
+class cVideoDirectory {
+private:
+  char *name, *stored, *adjusted;
+  int length, number, digits;
+public:
+  cVideoDirectory(void);
+  ~cVideoDirectory();
+  uint FreeMB(void);
+  const char *Name(void) { return name; }
+  const char *Stored(void) { return stored; }
+  int Length(void) { return length; }
+  bool IsDistributed(void) { return name != NULL; }
+  bool Next(void);
+  void Store(void);
+  const char *Adjust(const char *FileName);
+  };
+
+cVideoDirectory::cVideoDirectory(void)
+{
+  length = strlen(VideoDirectory);
+  name = (VideoDirectory[length - 1] == '0') ? strdup(VideoDirectory) : NULL;
+  stored = adjusted = NULL;
+  number = -1;
+  digits = 0;
+}
+
+cVideoDirectory::~cVideoDirectory()
+{
+  delete name;
+  delete stored;
+  delete adjusted;
+}
+
+uint cVideoDirectory::FreeMB(void)
+{
+  return FreeDiskSpaceMB(name ? name : VideoDirectory);
+}
+
+bool cVideoDirectory::Next(void)
+{
+  if (name) {
+     if (number < 0) {
+        int l = length;
+        while (l-- > 0 && isdigit(name[l]))
+              ;
+        l++;
+        digits = length - l;
+        int n = atoi(&name[l]);
+        if (n == 0)
+           number = n;
+        else
+           return false; // base video directory must end with zero
+        }
+     if (++number > 0) {
+        char buf[16];
+        if (sprintf(buf, "%0*d", digits, number) == digits) {
+           strcpy(&name[length - digits], buf);
+           return DirectoryOk(name);
+           }
+        }
+     }
+  return false;
+}
+
+void cVideoDirectory::Store(void)
+{
+  if (name) {
+     delete stored;
+     stored = strdup(name);
+     }
+}
+
+const char *cVideoDirectory::Adjust(const char *FileName)
+{
+  if (stored) {
+     delete adjusted;
+     adjusted = strdup(FileName);
+     return strncpy(adjusted, stored, length);
+     }
+  return NULL;
+}
+
+int OpenVideoFile(const char *FileName, int Flags)
+{
+  const char *ActualFileName = FileName;
+
+  // Incoming name must be in base video directory:
+  if (strstr(FileName, VideoDirectory) != FileName) {
+     esyslog(LOG_ERR, "ERROR: %s not in %s", FileName, VideoDirectory);
+     errno = ENOENT; // must set 'errno' - any ideas for a better value?
+     return -1;
+     }
+  // Are we going to create a new file?
+  if ((Flags & O_CREAT) != 0) {
+     cVideoDirectory Dir;
+     if (Dir.IsDistributed()) {
+        // Find the directory with the most free space:
+        uint MaxFree = Dir.FreeMB();
+        while (Dir.Next()) {
+              uint Free = FreeDiskSpaceMB(Dir.Name());
+              if (Free > MaxFree) {
+                 Dir.Store();
+                 MaxFree = Free;
+                 }
+              }
+        if (Dir.Stored()) {
+           ActualFileName = Dir.Adjust(FileName);
+           if (!MakeDirs(ActualFileName, false))
+              return -1; // errno has been set by MakeDirs()
+           if (symlink(ActualFileName, FileName) < 0) {
+              LOG_ERROR_STR(FileName);
+              return -1;
+              }
+           ActualFileName = strdup(ActualFileName); // must survive Dir!
+           }
+        }
+     }
+  int Result = open(ActualFileName, Flags, S_IRUSR | S_IWUSR);
+  if (ActualFileName != FileName)
+     delete ActualFileName;
+  return Result;
+}
+
+int CloseVideoFile(int FileHandle)
+{
+  // just in case we ever decide to do something special when closing the file!
+  return close(FileHandle);
+}
+
+bool RenameVideoFile(const char *OldName, const char *NewName)
+{
+  // Only the base video directory entry will be renamed, leaving the
+  // possible symlinks untouched. Going through all the symlinks and disks
+  // would be unnecessary work - maybe later...
+  if (rename(OldName, NewName) == -1) {
+     LOG_ERROR_STR(OldName);
+     return false;
+     }
+  return true;
+}
+
+bool RemoveVideoFile(const char *FileName)
+{
+  return RemoveFileOrDir(FileName, true);
+}
+
+bool VideoFileSpaceAvailable(unsigned int SizeMB)
+{
+  cVideoDirectory Dir;
+  if (Dir.IsDistributed()) {
+     if (Dir.FreeMB() >= SizeMB * 2) // base directory needs additional space
+        return true;
+     while (Dir.Next()) {
+           if (Dir.FreeMB() >= SizeMB)
+              return true;
+           }
+     return false;
+     }
+  return Dir.FreeMB() >= SizeMB;
+}