BSArch/04/bmp_fractal.c

/* Betriebssystem & Middleware
 *
 * Betriebssystemarchitektur SS 2006
 *
 * Uebung 4.4 
 */

// $Id: bmp_fractal.c,v 1.5 2006/07/01 12:19:46 joko Exp $

#include <windows.h>
#include <stdio.h>
#include <errno.h>

#define XSIZE 500
#define YSIZE 500
#include "algorithm.h"


/* BMP Header */
unsigned char header[54]={0x42,0x4d,              // signature BM
                            0xe6,0x71,0x0b,0x0,   // filesize 750054
                            0x0,0x0,0x0,0x0,      // reserved 
                            0x36,0x0,0x0,0x0,     // image offset 54
                            0x28,0x0,0x0,0x0,     // size of header follows 40
                            0xf4,0x1,0x0,0x0,     // with of image 500
                            0xf4,0x1,0x0,0x0,     // height of image 500
                            0x1,0x0,              // number of planes  1
                            0x18,0x0,             // number of pixel 24
                            0x0,0x0,0x0,0x0,      // compression  
                            0xb0,0x71,0x0b,0x0,   // size of image 750000
                            0x0,0x0,0x0,0x0,      // xres
                            0x0,0x0,0x0,0x0,      // yres   
                            0x0,0x0,0x0,0x0,      // number of colortables    
                            0x0,0x0,0x0,0x0       // number of important colors
                        };


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 {
  unsigned int start_row;
  unsigned int number_of_rows;
  unsigned char * pBitmap;
} WORKERARGS, *PWORKERARGS;

// worker thread - main entry function
DWORD WINAPI fractal_thread (LPVOID lpParam) {
  
  // thread stuff
  int thread_id;
  PWORKERARGS args;

  // fractal calculation
  int x, y;
  char bgr[3];

  thread_id = GetCurrentThreadId();
  
  // get worker arguments
  args = (PWORKERARGS)lpParam;
  
  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);
  
  // calculate fractal
  for (y = (args->start_row + args->number_of_rows) - 1; y >= args->start_row; 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]); 
      
      // debugging
      //printf("pointer: %p\n", pDataBitmapCurrent);
      
      // transfer color values to current pixel
      args->pBitmap[0] = bgr[0];
      args->pBitmap[1] = bgr[1];
      args->pBitmap[2] = bgr[2];
      
      // move pointer to next pixel
      args->pBitmap += 3;
      
    }
    //no padding required because 1500%4 =0
  }

  return 0;

}


int main(int argc, char *argv[]) {

  // MMF support
  DWORD err;
  HANDLE hMap, hFile;
  LPVOID pData;
  unsigned char *pDataBitmap, *pDataBitmapCurrent;

  // workers
  unsigned int workers = 3;
  unsigned int worker_index, worker_rows, worker_startrow;
  HANDLE *worker_handles;
  //struct WorkerArguments *worker_args;
  PWORKERARGS worker_args;

  
  // create empty bmp-file (black background)
  write_blank_file("test.bmp");

  /* 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, NULL);
  if (NULL == hMap) {
    printErrorAndExit("Error at CreateFileMapping", 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
  printf("pos. of file: %p\n", pData);
  printf("pos. of bitmap: %p\n", pDataBitmap);

  // pointer to current pixel
  pDataBitmapCurrent = pDataBitmap;

  /*
  // turn bitmap into white wand
  for (offset = 0; offset < 500 * 500 * 3; offset++) {
    //pDataBitmap[offset] = 255;
    *pDataBitmapCurrent = 255;
    pDataBitmapCurrent++;
  }
  */


  // 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);
  */
  // allocate memory for table of all worker arguments
  worker_args = (PWORKERARGS) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, workers * sizeof(WORKERARGS));
  
  // calculate segments of bitmap for worker threads/processes and start them
  worker_rows = YSIZE / workers;
  printf("rows for each worker: %i\n", worker_rows);
  for (worker_index = 0; worker_index < workers; worker_index++) {
    
    // 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;
      printf("rows for last worker: %i\n", worker_rows);
    }
    
    worker_args[worker_index].start_row = worker_startrow;
    worker_args[worker_index].number_of_rows = worker_rows;
    worker_args[worker_index].pBitmap = pDataBitmap;
    
    worker_handles[worker_index] = CreateThread(
      NULL,                          // LPSECURITY_ATTRIBUTES lpThreadAttributes,
      0,                             // SIZE_T dwStackSize,
      fractal_thread,                // LPTHREAD_START_ROUTINE lpStartAddress,
      &worker_args[worker_index],    // LPVOID lpParameter,
      0,                             // DWORD dwCreationFlags,
      NULL                           // LPDWORD lpThreadId
    );
    
  }

  // wait for all threads
  if (WaitForMultipleObjects(workers, worker_handles, TRUE, INFINITE) == WAIT_FAILED)
    perror("WaitForMultipleObjects");
  
  /* 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);
  }

}
1	/* Betriebssystem & Middleware
2	*
3	* Betriebssystemarchitektur SS 2006
4	*
5	* Uebung 4.4
6	*/
7
8	// $Id: bmp_fractal.c,v 1.5 2006/07/01 12:19:46 joko Exp $
9
10	#include <windows.h>
11	#include <stdio.h>
12	#include <errno.h>
13
14	#define XSIZE 500
15	#define YSIZE 500
16	#include "algorithm.h"
17
18
19	/* BMP Header */
20	unsigned char header[54]={0x42,0x4d, // signature BM
21	0xe6,0x71,0x0b,0x0, // filesize 750054
22	0x0,0x0,0x0,0x0, // reserved
23	0x36,0x0,0x0,0x0, // image offset 54
24	0x28,0x0,0x0,0x0, // size of header follows 40
25	0xf4,0x1,0x0,0x0, // with of image 500
26	0xf4,0x1,0x0,0x0, // height of image 500
27	0x1,0x0, // number of planes 1
28	0x18,0x0, // number of pixel 24
29	0x0,0x0,0x0,0x0, // compression
30	0xb0,0x71,0x0b,0x0, // size of image 750000
31	0x0,0x0,0x0,0x0, // xres
32	0x0,0x0,0x0,0x0, // yres
33	0x0,0x0,0x0,0x0, // number of colortables
34	0x0,0x0,0x0,0x0 // number of important colors
35	};
36
37
38	void printErrorAndExit(const char *msg, DWORD err) {
39	LPSTR lpMsgBuf;
40	if(FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER\|
41	FORMAT_MESSAGE_FROM_SYSTEM \|
42	FORMAT_MESSAGE_IGNORE_INSERTS,
43	NULL,
44	err,
45	MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
46	(LPTSTR) &lpMsgBuf,
47	0,
48	NULL ))
49	{
50	fprintf(stderr,"%s : %s\n",msg,lpMsgBuf);
51	LocalFree(lpMsgBuf);
52	}
53	else
54	{
55	fprintf(stderr,"Error at FormatMesage: %d\n",err=GetLastError());
56	}
57	exit(err);
58	}
59
60
61	void write_blank_file(char *filename) {
62
63	FILE *fd;
64	int len, i, img_size;
65
66	// open file handle
67	fd = fopen(filename, "wb+");
68	if (NULL == fd) {
69	perror("open");
70	exit(1);
71	}
72
73	// write bmp header to file
74	len = fwrite(header, 1, sizeof(header), fd);
75
76	// error checking
77	if (-1 == len \|\| len != sizeof(header)) {
78	perror("write");
79	exit(2);
80	}
81
82	// write three null-bytes for each pixel to file to create a black picture
83	img_size = XSIZE * YSIZE;
84	for (i = 0; i < img_size; i++) {
85	len = fwrite("\0\0\0", 1, 3, fd);
86	if (-1 == len \|\| len != 3) {
87	perror("write");
88	exit(4);
89	}
90	}
91
92	// close file handle
93	fclose(fd);
94	}
95
96
97	// arguments for each thread
98	typedef struct _WorkerArguments {
99	unsigned int start_row;
100	unsigned int number_of_rows;
101	unsigned char * pBitmap;
102	} WORKERARGS, *PWORKERARGS;
103
104	// worker thread - main entry function
105	DWORD WINAPI fractal_thread (LPVOID lpParam) {
106
107	// thread stuff
108	int thread_id;
109	PWORKERARGS args;
110
111	// fractal calculation
112	int x, y;
113	char bgr[3];
114
115	thread_id = GetCurrentThreadId();
116
117	// get worker arguments
118	args = (PWORKERARGS)lpParam;
119
120	printf("thread_id: %i\n", thread_id);
121	printf("arg.start_row: %i\n", args->start_row);
122	printf("arg.number_of_rows: %i\n", args->number_of_rows);
123
124	// calculate fractal
125	for (y = (args->start_row + args->number_of_rows) - 1; y >= args->start_row; y--) {
126	for (x = 0; x < XSIZE; x++) {
127	getColorValuesAt(x * (2.0 / XSIZE) - 1.5, y * (2.0 / YSIZE) - 1.0, &bgr[2], &bgr[1], &bgr[0]);
128
129	// debugging
130	//printf("pointer: %p\n", pDataBitmapCurrent);
131
132	// transfer color values to current pixel
133	args->pBitmap[0] = bgr[0];
134	args->pBitmap[1] = bgr[1];
135	args->pBitmap[2] = bgr[2];
136
137	// move pointer to next pixel
138	args->pBitmap += 3;
139
140	}
141	//no padding required because 1500%4 =0
142	}
143
144	return 0;
145
146	}
147
148
149	int main(int argc, char *argv[]) {
150
151	// MMF support
152	DWORD err;
153	HANDLE hMap, hFile;
154	LPVOID pData;
155	unsigned char pDataBitmap, pDataBitmapCurrent;
156
157	// workers
158	unsigned int workers = 3;
159	unsigned int worker_index, worker_rows, worker_startrow;
160	HANDLE *worker_handles;
161	//struct WorkerArguments *worker_args;
162	PWORKERARGS worker_args;
163
164
165	// create empty bmp-file (black background)
166	write_blank_file("test.bmp");
167
168	/* open file for reading and writing */
169	hFile = CreateFile("test.bmp", GENERIC_WRITE\|GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
170	if (INVALID_HANDLE_VALUE == hFile) {
171	err = GetLastError();
172	printErrorAndExit("Error at CreateFile",err);
173	}
174
175	/* create the file mapping object */
176	hMap = CreateFileMapping(hFile, NULL, PAGE_READWRITE, 0, 0, NULL);
177	if (NULL == hMap) {
178	printErrorAndExit("Error at CreateFileMapping", GetLastError());
179	}
180
181	/* map the whole file into the process context */
182	pData = MapViewOfFile(hMap, FILE_MAP_WRITE, 0, 0, 0);
183	if (NULL == pData) {
184	printErrorAndExit("Error at MapViewOfFile", GetLastError());
185	}
186
187
188	// calculate pointer to beginning of bitmap
189	pDataBitmap = (unsigned char *)((INT_PTR)pData + sizeof(header));
190
191	// debugging
192	printf("pos. of file: %p\n", pData);
193	printf("pos. of bitmap: %p\n", pDataBitmap);
194
195	// pointer to current pixel
196	pDataBitmapCurrent = pDataBitmap;
197
198	/*
199	// turn bitmap into white wand
200	for (offset = 0; offset < 500 * 500 * 3; offset++) {
201	//pDataBitmap[offset] = 255;
202	*pDataBitmapCurrent = 255;
203	pDataBitmapCurrent++;
204	}
205	*/
206
207
208	// allocate memory for table of all worker handles
209	if ((worker_handles = malloc(workers * sizeof worker_handles[0])) == NULL)
210	perror("malloc"), exit(1);
211
212	/*
213	// allocate memory for table of all worker arguments
214	if ((worker_args = malloc(workers * sizeof worker_args[0])) == NULL)
215	perror("malloc"), exit(1);
216	*/
217	// allocate memory for table of all worker arguments
218	worker_args = (PWORKERARGS) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, workers * sizeof(WORKERARGS));
219
220	// calculate segments of bitmap for worker threads/processes and start them
221	worker_rows = YSIZE / workers;
222	printf("rows for each worker: %i\n", worker_rows);
223	for (worker_index = 0; worker_index < workers; worker_index++) {
224
225	// number of row to start for each worker
226	worker_startrow = worker_index * worker_rows;
227
228	// recalculate number of rows for last worker if (YSIZE mod workers) != 0
229	if (worker_index == workers - 1) {
230	worker_rows = YSIZE - worker_startrow;
231	printf("rows for last worker: %i\n", worker_rows);
232	}
233
234	worker_args[worker_index].start_row = worker_startrow;
235	worker_args[worker_index].number_of_rows = worker_rows;
236	worker_args[worker_index].pBitmap = pDataBitmap;
237
238	worker_handles[worker_index] = CreateThread(
239	NULL, // LPSECURITY_ATTRIBUTES lpThreadAttributes,
240	0, // SIZE_T dwStackSize,
241	fractal_thread, // LPTHREAD_START_ROUTINE lpStartAddress,
242	&worker_args[worker_index], // LPVOID lpParameter,
243	0, // DWORD dwCreationFlags,
244	NULL // LPDWORD lpThreadId
245	);
246
247	}
248
249	// wait for all threads
250	if (WaitForMultipleObjects(workers, worker_handles, TRUE, INFINITE) == WAIT_FAILED)
251	perror("WaitForMultipleObjects");
252
253	/* write the result into the file */
254	if (!FlushViewOfFile(pData, 0)) {
255	err = GetLastError();
256	printErrorAndExit("Error at UnmapViewOfFile", err);
257	}
258
259	/* remove the mapped file */
260	if (!UnmapViewOfFile(pData)) {
261	err = GetLastError();
262	printErrorAndExit("Error at UnmapViewOfFile", err);
263	exit(err);
264	}
265
266	/* cleanup handles */
267	if (!CloseHandle(hMap) \|\| !CloseHandle(hFile) ) {
268	err = GetLastError();
269	printErrorAndExit("Error at CloseHandle", err);
270	}
271
272	}
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