2 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
3 SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO
4 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
5 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
6 IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
7 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
8 FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
9 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
10 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
11 COPYRIGHT 1993-1999 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
29 int dpmi_find_dos_memory()
33 memset(&r,0,sizeof(r));
34 r.x.eax = 0x0100; // DPMI allocate DOS memory
35 r.x.ebx = 0xffff; // Number of paragraphs requested
36 int386 (0x31, &r, &r);
37 //if ( (r.x.eax & 0xffff) == 0x08 )
38 //if ( (r.x.eax & 0xffff) == 0x08 )
40 return ((r.x.ebx & 0xffff)*16);
45 void *dpmi_real_malloc( int size, ushort *selector )
49 memset(&r,0,sizeof(r));
50 r.x.eax = 0x0100; // DPMI allocate DOS memory
51 r.x.ebx = (size + 15) >> 4; // Number of paragraphs requested
52 int386 (0x31, &r, &r);
54 if (r.x.cflag) // Failed
58 *selector = r.x.edx & 0xFFFF;
60 return (void *) ((r.x.eax & 0xFFFF) << 4);
63 void dpmi_real_free( ushort selector )
67 memset(&r,0,sizeof(r));
68 r.x.eax = 0x0101; // DPMI free DOS memory
69 r.x.ebx = selector; // Selector to free
70 int386 (0x31, &r, &r);
74 void dpmi_real_int386x( ubyte intno, dpmi_real_regs * rregs )
79 /* Use DMPI call 300h to issue the DOS interrupt */
81 memset(®s,0,sizeof(regs));
82 memset(&sregs,0,sizeof(sregs));
87 sregs.es = FP_SEG(rregs);
88 regs.x.edi = FP_OFF(rregs);
89 int386x( 0x31, ®s, ®s, &sregs );
92 int dos_stack_initialized = 0;
93 ubyte * dos_stack = NULL;
94 ubyte * dos_stack_top = NULL;
95 #define DOS_STACK_SIZE (4*1024) // A big ol' 4K stack!!!
97 void dpmi_real_call(dpmi_real_regs * rregs)
103 if ( !dos_stack_initialized ) {
104 dos_stack_initialized = 1;
105 dos_stack = dpmi_real_malloc( DOS_STACK_SIZE, &temp_selector );
106 if ( dos_stack == NULL ) {
107 printf( "Error allocating real mode stack!\n" );
108 dos_stack_top = NULL;
110 dos_stack_top = &dos_stack[DOS_STACK_SIZE];
114 // Give this puppy a stack!!!
115 if ( dos_stack_top ) {
116 rregs->ss = DPMI_real_segment(dos_stack_top);
117 rregs->sp = DPMI_real_offset(dos_stack_top);
120 /* Use DMPI call 301h to call real mode procedure */
121 memset(®s,0,sizeof(regs));
122 memset(&sregs,0,sizeof(sregs));
126 sregs.es = FP_SEG(rregs);
127 regs.x.edi = FP_OFF(rregs);
128 int386x( 0x31, ®s, ®s, &sregs );
130 Error("bad return value <%x> in dpmi_call_real()", regs.w.ax);
135 int dpmi_unlock_region(void *address, unsigned length)
140 linear = (unsigned int) address;
142 total_bytes -= length;
143 //mprintf( 1, "DPMI unlocked %d bytes\n", total_bytes );
145 memset(®s,0,sizeof(regs));
146 regs.w.ax = 0x601; // DPMI Unlock Linear Region
147 regs.w.bx = (linear >> 16); // Linear address in BX:CX
148 regs.w.cx = (linear & 0xFFFF);
150 regs.w.si = (length >> 16); // Length in SI:DI
151 regs.w.di = (length & 0xFFFF);
152 int386 (0x31, ®s, ®s);
153 return (! regs.w.cflag); // Return 0 if can't lock
156 int dpmi_lock_region(void *address, unsigned length)
163 linear = (unsigned int) address;
165 total_bytes += length;
166 //mprintf( 1, "DPMI Locked down %d bytes\n", total_bytes );
168 memset(®s,0,sizeof(regs));
169 regs.w.ax = 0x600; // DPMI Lock Linear Region
170 regs.w.bx = (linear >> 16); // Linear address in BX:CX
171 regs.w.cx = (linear & 0xFFFF);
173 regs.w.si = (length >> 16); // Length in SI:DI
174 regs.w.di = (length & 0xFFFF);
175 int386 (0x31, ®s, ®s);
176 return (! regs.w.cflag); // Return 0 if can't lock
180 int dpmi_modify_selector_base( ushort selector, void * address )
185 linear = (unsigned int)address;
187 memset(®s,0,sizeof(regs));
188 regs.w.ax = 0x0007; // DPMI Change Selector Base Addres
189 regs.w.bx = selector; // Selector to change
190 regs.w.cx = (linear >> 16); // Base address
191 regs.w.dx = (linear & 0xFFFF);
192 int386 (0x31, ®s, ®s); // call dpmi
194 return 0; // Return 0 if error
200 int dpmi_modify_selector_limit( ushort selector, int size )
203 unsigned int segment_limit;
205 segment_limit = (unsigned int) size;
207 memset(®s,0,sizeof(regs));
208 regs.w.ax = 0x0008; // DPMI Change Selector Limit
209 regs.w.bx = selector; // Selector to change
210 regs.w.cx = (segment_limit >> 16); // Size of selector
211 regs.w.dx = (segment_limit & 0xFFFF);
212 int386 (0x31, ®s, ®s); // call dpmi
214 return 0; // Return 0 if error
220 int dpmi_allocate_selector( void * address, int size, ushort * selector )
225 memset(®s,0,sizeof(regs));
226 regs.w.ax = 0; // DPMI Allocate Selector
227 regs.w.cx = 1; // Allocate 1 selector
228 int386 (0x31, ®s, ®s); // call dpmi
230 return 0; // Return 0 if error
231 *selector = regs.w.ax;
233 if ( !dpmi_modify_selector_base( *selector, address ) )
236 if ( !dpmi_modify_selector_limit( *selector, size ) )
239 // mprintf( 0, "Selector 0x%4x has base of 0x%8x, size %d bytes\n", *selector, linear,segment_limit);
244 static void * dpmi_dos_buffer = NULL;
245 static ushort dpmi_dos_selector = 0;
249 if (dpmi_dos_selector!=0) {
250 dpmi_dos_buffer = NULL;
251 dpmi_dos_selector = 0;
255 typedef struct mem_data {
256 int largest_block_bytes;
257 int max_unlocked_page_allocation;
258 int largest_lockable_pages;
261 int unused_physical_pages;
262 int total_physical_pages;
263 int free_linear_pages;
264 int paging_size_pages;
268 unsigned int dpmi_virtual_memory=0;
269 unsigned int dpmi_available_memory=0;
270 unsigned int dpmi_physical_memory=0;
271 unsigned int dpmi_dos_memory = 0;
273 extern void cdecl _GETDS();
274 extern void cdecl cstart_();
276 int dpmi_init(int verbose)
282 dpmi_dos_memory = dpmi_find_dos_memory();
284 dpmi_dos_buffer = dpmi_real_malloc( 1024, &dpmi_dos_selector);
285 if (!dpmi_dos_buffer) {
286 dpmi_dos_selector = 0;
287 Error( "Error allocating 1K of DOS memory\n" );
292 memset(®s,0,sizeof(regs));
293 regs.x.eax = 0x400; // DPMI Get Memory Info
294 int386( 0x31, ®s, ®s );
296 if (verbose) printf( "V%d.%d, CPU:%d, VMM:", regs.h.ah, regs.h.al, regs.h.cl );
298 if (verbose) printf( "1" );
299 dpmi_virtual_memory = 1;
301 if (verbose) printf( "0" );
305 //--------- Find available memory
306 memset(®s,0,sizeof(regs));
307 memset(&sregs,0,sizeof(sregs));
308 regs.x.eax = 0x500; // DPMI Get Memory Info
309 sregs.es = FP_SEG(&mi);
310 regs.x.edi = FP_OFF(&mi);
311 int386x( 0x31, ®s, ®s, &sregs );
313 if (verbose) printf( ", P:%dK", mi.largest_lockable_pages*4 );
314 if (dpmi_virtual_memory)
315 if (verbose) printf( ", A:%dK", mi.largest_block_bytes/1024 );
316 //dpmi_physical_memory = mi.largest_lockable_pages*4096;
317 //dpmi_available_memory = mi.largest_block_bytes;
318 dpmi_physical_memory = mi.total_physical_pages*4096;
319 dpmi_available_memory = mi.total_pages * 4096;
321 if (verbose) printf( "MemInfo failed!" );
322 dpmi_physical_memory = 16*1024*1024; // Assume 16 MB
323 dpmi_available_memory = 16*1024*1024; // Assume 16 MB
326 if (!dpmi_lock_region( _GETDS, 4096 )) {
327 Error( "Can't lock _GETDS" );
329 if (!dpmi_lock_region( cstart_, 4096 )) {
330 Error( "Can't lock cstart" );
332 if (!dpmi_lock_region( _chain_intr, 4096 )) {
333 Error( "Can't lock _chain_intr" );
338 void *dpmi_get_temp_low_buffer( int size )
340 if ( dpmi_dos_buffer == NULL ) return NULL;
341 if ( size > 1024 ) return NULL;
343 return dpmi_dos_buffer;
346 int dpmi_set_pm_handler(unsigned intnum, void far * isr )
350 /* Use DMPI call 204h to get pm interrrupt */
351 memset(®s,0,sizeof(regs));
354 regs.w.cx = FP_SEG(isr);
355 regs.x.edx = FP_OFF(isr);
356 int386( 0x31, ®s, ®s );