--- joko/Uni/BSArch/04/bmp_fractal.c	2006/06/30 20:39:33	1.1
+++ joko/Uni/BSArch/04/bmp_fractal.c	2006/07/02 01:51:26	1.10
@@ -4,6 +4,10 @@
  *
  * Uebung 4.4 
  */
+
+// $Id: bmp_fractal.c,v 1.10 2006/07/02 01:51:26 joko Exp $
+
+#include <windows.h>
 #include <stdio.h>
 #include <errno.h>
 
@@ -11,7 +15,12 @@
 #define YSIZE 500
 #include "algorithm.h"
 
-/* BMP Header 
+#define MASTER -1
+
+BOOL VERBOSE = TRUE;
+
+
+/* BMP Header */
 unsigned char header[54]={0x42,0x4d,              // signature BM
                             0xe6,0x71,0x0b,0x0,   // filesize 750054
                             0x0,0x0,0x0,0x0,      // reserved 
@@ -28,94 +37,358 @@
                             0x0,0x0,0x0,0x0,      // number of colortables    
                             0x0,0x0,0x0,0x0       // number of important colors
                         };
-*/
 
-int main(int argc, char *argv[])
-{
-    FILE *fd;
-    int len,x,y;
-    char bgr[3];
-    short svalue;
-    int   lvalue;
-    unsigned char header[54],*ptr=&header[0];
-      
-    fd=fopen("test.bmp","wb+");
-    if(NULL==fd)
-    {
-        perror("open"); exit(1);
-    }
-/* Der folgende Abschnitt dient nur zur information und kann durch 
-    schreiben der auskommentierten Variable header ersetzt werden */    
-    svalue=0x4d42;
-    memcpy(ptr,&svalue,2);//signatur
-    ptr+=2;
-    lvalue=XSIZE*YSIZE*3+54;
-    memcpy(ptr,&lvalue,4); //filesize
-    ptr+=4;
-    lvalue=0;
-    memcpy(ptr,&lvalue,4);//reserved
-    ptr+=4;
-    lvalue=54;
-    memcpy(ptr,&lvalue,4);//image offset
-    ptr+=4;
-    lvalue=40;
-    memcpy(ptr,&lvalue,4);//size of header follows
-    ptr+=4;
-    lvalue=XSIZE;
-    memcpy(ptr,&lvalue,4);//with of image
-    ptr+=4;
-    lvalue=YSIZE;
-    memcpy(ptr,&lvalue,4); //height of image
-    ptr+=4;
-    svalue=1;
-    memcpy(ptr,&svalue,2); //number of planes
-    ptr+=2;
-    svalue=24;
-    memcpy(ptr,&svalue,2); //number of pixel
-    ptr+=2;
-    lvalue=0; //compression
-    memcpy(ptr,&lvalue,4); //compression
-    ptr+=4;
-    lvalue=XSIZE*YSIZE*3; 
-    memcpy(ptr,&lvalue,4); //size of image
-    ptr+=4;
-    lvalue=0;
-    memcpy(ptr,&lvalue,4); //xres  
-    ptr+=4;
-    lvalue=0;
-    memcpy(ptr,&lvalue,4); //yres
-    ptr+=4;
-    lvalue=0;
-    memcpy(ptr,&lvalue,4); //number of colortables
-    ptr+=4;
-    lvalue=0;
-    memcpy(ptr,&lvalue,4); //number of important colors
-    ptr+=4;
-/* Ende Information */
-
-    len=fwrite(header,1,sizeof(header),fd); //write header
-    
-    if(-1==len || len!=sizeof(header))
-    {
-        perror("write");
-        exit(2);
-    }
-    
-    for(y=YSIZE-1;y>=0;y--)
-    {
-            for(x=0;x<XSIZE;x++)
-            {
-                getColorValuesAt(x * (2.0 / XSIZE) - 1.5, y * (2.0 / YSIZE) - 1.0,&bgr[2],&bgr[1],&bgr[0]); 
-                
-                len=fwrite(bgr,1,3,fd);
-                if(-1==len || len!=3)
-                {
-                    perror("write");
-                    exit(4);
-                }
-            }
-            /*no padding required because 1500%4 =0*/
-    }        
-    fclose(fd);
+
+void printErrorAndExit(const char *msg, DWORD err) {
+	LPSTR lpMsgBuf;
+	if(FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER|
+			          FORMAT_MESSAGE_FROM_SYSTEM | 
+					  FORMAT_MESSAGE_IGNORE_INSERTS,
+						NULL,
+						err,
+					  MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
+					  (LPTSTR) &lpMsgBuf,
+					  0,
+					  NULL ))
+	{
+		fprintf(stderr,"%s : %s\n",msg,lpMsgBuf);
+		LocalFree(lpMsgBuf);
+	}
+	else
+	{
+		fprintf(stderr,"Error at FormatMesage: %d\n",err=GetLastError());
+	}
+	exit(err);
+}
+
+
+void write_blank_file(char *filename) {
+
+  FILE *fd;
+  int len, i, img_size;
+
+  // open file handle
+  fd = fopen(filename, "wb+");
+  if (NULL == fd) {
+    perror("open");
+    exit(1);
+  }
+
+  // write bmp header to file
+  len = fwrite(header, 1, sizeof(header), fd);
+  
+  // error checking
+  if (-1 == len || len != sizeof(header)) {
+    perror("write");
+    exit(2);
+  }
+  
+  // write three null-bytes for each pixel to file to create a black picture
+  img_size = XSIZE * YSIZE;
+  for (i = 0; i < img_size; i++) {
+    len = fwrite("\0\0\0", 1, 3, fd);
+    if (-1 == len || len != 3) {
+      perror("write");
+      exit(4);
+    }
+  }
+  
+  // close file handle
+  fclose(fd);
+}
+
+
+// arguments for each thread
+typedef struct _WorkerArguments {
+  int start_row;
+  int number_of_rows;
+  unsigned char * pBitmap;
+} WORKERARGS, *PWORKERARGS;
+
+// worker thread - main entry function
+DWORD WINAPI fractal_create_segment (LPVOID lpParam) {
+  
+  // thread stuff
+  int thread_id;
+  PWORKERARGS args;
+  unsigned char *pDataBitmapSegment;
+
+  // fractal calculation
+  int x, y;
+  char bgr[3];
+
+  thread_id = GetCurrentThreadId();
+  
+  // get worker arguments
+  args = (PWORKERARGS)lpParam;
+
+  // calculate pointer to beginning of segment
+  pDataBitmapSegment = (unsigned char *)((INT_PTR)args->pBitmap + (YSIZE - (args->start_row + args->number_of_rows)) * 3 * XSIZE);
+
+  // debugging
+  if (VERBOSE) {
+    printf("----------------------------------------------\n");
+    printf("thread_id: %i\n", thread_id);
+    printf("arg.start_row: %i\n", args->start_row);
+    printf("arg.number_of_rows: %i\n", args->number_of_rows);
+    printf("segment_start: %p\n", pDataBitmapSegment);
+  }
+  
+  // calculate fractal
+  for (y = (args->start_row + args->number_of_rows) - 1; y >= args->start_row; y--) {
+    //printf("calc: thread=%i; y=%i            limits: %i,%i    p: %p\n", thread_id, y, args->start_row, args->number_of_rows, pDataBitmapSegment);
+    for (x = 0; x < XSIZE; x++) {
+      getColorValuesAt(x * (2.0 / XSIZE) - 1.5, y * (2.0 / YSIZE) - 1.0, &bgr[2], &bgr[1], &bgr[0]); 
+      
+      // transfer color values to current pixel
+      pDataBitmapSegment[0] = bgr[0];
+      pDataBitmapSegment[1] = bgr[1];
+      pDataBitmapSegment[2] = bgr[2];
+      
+      // move pointer to next pixel
+      pDataBitmapSegment += 3;
+      
+    }
+    //no padding required because 1500%4 =0 ???
+  }
+
+  if (VERBOSE)
+    printf("thread finished: %i\n", thread_id);
+  return 0;
+
+}
+
+
+int main(int argc, char *argv[]) {
+
+  // MMF support
+  DWORD err;
+  HANDLE hMap, hFile;
+  LPVOID pData;
+  unsigned char *pDataBitmap;
+
+  // workers
+  int workers = 5;
+  int worker_index, worker_rows, worker_startrow;
+  HANDLE *worker_handles;
+  PWORKERARGS worker_args;
+
+  // threads or processes?
+  BOOL use_processes = TRUE;
+  int worker_id = MASTER;
+  
+  // information for creating processes
+  STARTUPINFO si;
+  PROCESS_INFORMATION pi;
+  char szCmdline[1024];
+  
+  
+  // "parse" command line arguments
+  if (argc >= 2) {
+    worker_id = atoi(argv[1]);
+  }
+  
+  if (VERBOSE) {
+    printf("==============================================================\n");
+    printf("worker-id: %i\n", worker_id);
+  }
+  
+  // create empty bmp-file (black background)
+  if (worker_id == MASTER)
+    write_blank_file("test.bmp");
+
+  if (worker_id == MASTER) {
+    
+    /* open file for reading and writing */
+    hFile = CreateFile("test.bmp", GENERIC_WRITE|GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+    if (INVALID_HANDLE_VALUE == hFile) {
+      err = GetLastError();
+      printErrorAndExit("Error at CreateFile",err);
+    }
+
+    /* create the file mapping object */
+    hMap = CreateFileMapping(hFile, NULL, PAGE_READWRITE, 0, 0, "bmp_fractal");
+    if (NULL == hMap) {
+      printErrorAndExit("Error at CreateFileMapping", GetLastError());
+    }
+    
+  } else {
+    
+    // open existing mapping object
+    hMap = OpenFileMapping(FILE_MAP_WRITE, FALSE, "bmp_fractal");
+    if (NULL == hMap)
+      printErrorAndExit("Error at OpenFileMapping", GetLastError());
+  }
+  
+  /* map the whole file into the process context */
+  pData = MapViewOfFile(hMap, FILE_MAP_WRITE, 0, 0, 0);
+  if (NULL == pData) {
+    printErrorAndExit("Error at MapViewOfFile", GetLastError());
+  }
+
+  
+  // calculate pointer to beginning of bitmap
+  pDataBitmap = (unsigned char *)((INT_PTR)pData + sizeof(header));
+  
+  // debugging
+  if (VERBOSE) {
+    printf("pos. of file: %p\n", pData);
+    printf("pos. of bitmap: %p\n", pDataBitmap);
+  }
+
+  
+  if (use_processes && worker_id != MASTER) {  
+  
+    if (VERBOSE)
+      printf("inside worker-process\n");
+    
+    worker_index = worker_id;
+    
+    worker_startrow = atoi(argv[2]);
+    worker_rows = atoi(argv[3]);
+    
+    // allocate memory for one worker's arguments
+    if ((worker_args = malloc(sizeof(worker_args[0]))) == NULL)
+      perror("malloc"), exit(1);
+    
+    // assign worker's arguments
+    worker_args[0].start_row = worker_startrow;
+    worker_args[0].number_of_rows = worker_rows;
+    worker_args[0].pBitmap = pDataBitmap;
+
+    fractal_create_segment(&worker_args[0]);
     
+    return 0; 
+  }
+  
+  /*
+  // turn bitmap into white canvas
+  for (offset = 0; offset < 500 * 500 * 3; offset++) {
+    *pDataBitmap = 255;
+    pDataBitmap++;
+  }
+  exit(0);
+  */
+
+  // allocate memory for bitmap
+  /*
+  if ((pDataBitmap = malloc(XSIZE * YSIZE * 3 * sizeof(pDataBitmap[0]))) == NULL)
+    perror("malloc"), exit(1);
+  */
+  
+  // allocate memory for table of all worker handles
+  if ((worker_handles = malloc(workers * sizeof(worker_handles[0]))) == NULL)
+    perror("malloc"), exit(1);
+
+  // allocate memory for table of all worker arguments
+  if ((worker_args = malloc(workers * sizeof(worker_args[0]))) == NULL)
+    perror("malloc"), exit(1);
+  
+  
+  // calculate bitmap segment length for workers
+  worker_rows = YSIZE / workers;
+  if (VERBOSE)
+    printf("rows for each worker: %i\n", worker_rows);
+  
+  // start workers
+  for (worker_index = 0; worker_index < workers; worker_index++) {
+    
+    // debugging: just run single thread
+    //if (worker_index == 1)
+    //  continue;
+    
+    // number of row to start for each worker
+    worker_startrow = worker_index * worker_rows;
+    
+    // recalculate number of rows for last worker if (YSIZE mod workers) != 0
+    if (worker_index == workers - 1) {
+      worker_rows = YSIZE - worker_startrow;
+      if (VERBOSE)
+        printf("rows for last worker: %i\n", worker_rows);
+    }
+    
+    // assign each worker's arguments
+    worker_args[worker_index].start_row = worker_startrow;
+    worker_args[worker_index].number_of_rows = worker_rows;
+    worker_args[worker_index].pBitmap = pDataBitmap;
+    
+    if (!use_processes) {
+    
+      worker_handles[worker_index] = CreateThread(
+        NULL,                          // LPSECURITY_ATTRIBUTES lpThreadAttributes,
+        0,                             // SIZE_T dwStackSize,
+        &fractal_create_segment,                // LPTHREAD_START_ROUTINE lpStartAddress,
+        &worker_args[worker_index],    // LPVOID lpParameter,
+        0,                             // DWORD dwCreationFlags,
+        NULL                           // LPDWORD lpThreadId
+      );
+
+      if (!worker_handles[worker_index]) 
+        printErrorAndExit("CreateThread failed", GetLastError());
+      
+    } else {
+
+      _snprintf(szCmdline, 1023, "%s %i %i %i", argv[0], worker_index + 1, worker_startrow, worker_rows);
+      ZeroMemory( &si, sizeof(si) );
+      si.cb = sizeof(si);
+      ZeroMemory( &pi, sizeof(pi) );
+      
+      if (!CreateProcess(
+          NULL,           // No module name (use command line)
+          szCmdline,      // Command line
+          NULL,           // Process handle not inheritable
+          NULL,           // Thread handle not inheritable
+          FALSE,          // Set handle inheritance to FALSE
+          0,              // No creation flags
+          NULL,           // Use parent's environment block
+          NULL,           // Use parent's starting directory 
+          &si,            // Pointer to STARTUPINFO structure
+          &pi             // Pointer to PROCESS_INFORMATION structure
+      ))
+        printErrorAndExit("CreateProcess failed", GetLastError());
+    
+      worker_handles[worker_index] = pi.hProcess;
+      
+    }
+
+  }
+
+  // wait for all threads
+  if (VERBOSE)
+    printf("waiting for workers to finish...\n");
+  if (WaitForMultipleObjects(workers, worker_handles, TRUE, INFINITE) == WAIT_FAILED)
+    perror("WaitForMultipleObjects");
+
+  // debugging: just run single thread
+  //if (WaitForSingleObject(worker_handles[0], INFINITE) == WAIT_FAILED)
+  //  perror("WaitForSingleObject");
+
+  // close all worker handles
+  for (worker_index = 0; worker_index < workers; worker_index++)
+    CloseHandle(worker_handles[worker_index]);
+    
+  /* write the result into the file */
+  if (!FlushViewOfFile(pData, 0)) {
+    err = GetLastError();
+    printErrorAndExit("Error at UnmapViewOfFile", err);
+  }
+
+  /* remove the mapped file */
+  if (!UnmapViewOfFile(pData)) {
+    err = GetLastError();
+    printErrorAndExit("Error at UnmapViewOfFile", err);
+    exit(err);
+  }
+  
+  /* cleanup handles */
+  if (!CloseHandle(hMap) || !CloseHandle(hFile) ) {
+    err = GetLastError();
+    printErrorAndExit("Error at CloseHandle", err);
+  }
+
+  free(worker_args);
+  free(worker_handles);
+  
+  return 0;
+  
 }