1 files changed, 108 insertions, 0 deletions

diff --git a/noncore/apps/opie-reader/ppm_expander.cpp b/noncore/apps/opie-reader/ppm_expander.cpp
new file mode 100644
index 0000000..4f0a277
--- a/dev/null
+++ b/noncore/apps/opie-reader/ppm_expander.cpp
@@ -0,0 +1,108 @@
+/*
+ * Interface pour le programme de compression
+ * (c) 1995 Fabrice Bellard
+ */
+
+#include <stdlib.h>
+//#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+
+/***************************************************************************
+ * Interface avec les routines de compression
+ */
+
+#define METHOD_NB      2   /* nombre total de méthodes de compression */
+
+#define METHOD_STORE   0
+#define METHOD_PPM     1
+
+
+#define DEFAULT_SUFFIX  ".st"    /* extension par défault */
+/* signature en début de fichier */
+#define STAT_MAGIC_SIZE 4
+char stat_magic[STAT_MAGIC_SIZE]={'P','P','M','S'};
+
+#include "ppm_expander.h"
+
+ppm_expander::~ppm_expander() {
+  if (needppmend) ppm.PPM_End();
+  ppm.arith.Arith_DecodeEnd();
+  if (buf_in!=NULL) delete [] buf_in;
+  if (buf_out!=NULL) delete [] buf_out;
+  if (my_read_buf != NULL) delete my_read_buf;
+  if (my_file_in != NULL) fclose(my_file_in);
+}
+
+int ppm_expander::openfile(const char* infile)
+{
+  my_file_in=fopen(infile,"rb");
+  my_read_buf = new PPM_ReadBuf(my_file_in);
+  return home();
+}
+
+void ppm_expander::sizes(unsigned long& file, unsigned long& text)
+{
+  struct stat _stat;
+  fstat(fileno(my_file_in),&_stat);
+  file = _stat.st_size;
+  text = numblocks*blocksize;
+}
+
+int ppm_expander::home()
+{
+  fseek(my_file_in,0, SEEK_SET);
+  unsigned char header[STAT_MAGIC_SIZE];
+  size_t len=fread(header,1,STAT_MAGIC_SIZE,my_file_in);
+  if (strncmp((char*)header,stat_magic,STAT_MAGIC_SIZE)!=0)  {
+    return 1;
+  }
+  if (len!=(STAT_MAGIC_SIZE))  {
+    return 1;
+  }
+  if (fread(&maxnode,sizeof(maxnode),1,my_file_in) != 1) return 1;
+  if (fread(&blocksize,sizeof(blocksize),1,my_file_in) != 1) return 1;
+  if (fread(&numblocks,sizeof(numblocks),1,my_file_in) != 1) return 1;
+  //fprintf(stderr,"<%u,%u,%u>\n",maxnode,blocksize,numblocks);
+  int err = locate(0,0);
+  outbytes = 0;
+  return err;
+}
+
+void ppm_expander::locate(unsigned int n) {
+  locate(n/blocksize, n%blocksize);
+  outbytes = n;
+}
+
+int ppm_expander::locate(unsigned short block, unsigned int n)
+{
+  if (needppmend)
+    {
+      ppm.PPM_End();
+      needppmend = false;
+    }
+  size_t fpos;
+  fseek(my_file_in,STAT_MAGIC_SIZE+sizeof(maxnode)+sizeof(blocksize)+sizeof(numblocks)+block*sizeof(fpos),SEEK_SET);
+  if (fread(&fpos,sizeof(fpos),1,my_file_in) != 1) return 1;
+  fseek(my_file_in,fpos,SEEK_SET);
+
+  ppm.arith.Arith_DecodeInit(my_read_buf,buf_in,bufsize);
+  int err=ppm.PPM_Init(maxnode);
+  needppmend = true;
+  curblock = block;
+  for (int i = 0; i < n; i++) getch();
+}
+
+int ppm_expander::getch() {
+  if (curblock >= numblocks) return EOF;
+  int c=ppm.PPM_Decode();
+  if (c == SYM_EOF)
+    {
+      if (++curblock >= numblocks) return EOF;
+      locate(curblock,0);
+      c = ppm.PPM_Decode();
+    }
+  outbytes++;
+  return (c==SYM_EOF) ? EOF : c;
+}