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Use dos/sys compression if the uncompressed kernel is less than 64K. That

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makes the compressed kernel about 2K smaller.


git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1329 6ac86273-5f31-0410-b378-82cca8765d1b
This commit is contained in:
Bart Oldeman 2007-05-26 21:20:58 +00:00
parent ad58440395
commit 29d6eb79f1
2 changed files with 85 additions and 45 deletions
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5
kernel/makefile
View File

@ -38,9 +38,10 @@ production: ..\bin\$(TARGET).sys
kernel.sys: kernel.exe ..\utils\exeflat.exe
..\utils\exeflat kernel.exe kernelf.exe 0x60 -S0x10 -S0x74 -E
$(XUPX) kernelf.exe
if exist kernelf.exe $(XUPX) kernelf.exe
if exist kernelf.sys $(XUPX) kernelf.sys
..\utils\exeflat kernelf.exe kernel.sys 0x60 $(UPXOPT)
-$(RM) kernelf.exe
-$(RM) kernelf.exe kernelf.sys
kernel.exe: $(TARGET).lnk $(OBJS) $(LIBS)
$(LINK) @$(TARGET).lnk;

55
utils/exeflat.c
View File

@ -48,10 +48,13 @@ large portions copied from task.c
#include "exe.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#define BUFSIZE 32768u
#define KERNEL_START 0x10 /* the kernel code really starts here at 60:10 */
typedef struct {
UWORD off, seg;
} farptr;
@ -82,7 +85,7 @@ void usage(void)
int main(int argc, char **argv)
{
exe_header header;
static exe_header header; /* must be initialized to zero */
int i, j;
size_t bufsize;
farptr *reloc;
@ -92,7 +95,7 @@ int main(int argc, char **argv)
UBYTE **curbuf;
FILE *src, *dest;
short silentSegments[20], silentcount = 0, silentdone = 0;
int UPX = FALSE, flat_exe = FALSE;
int UPX = FALSE, flat_exe = FALSE, compress_sys_file = FALSE;
/* if no arguments provided, show usage and exit */
if (argc < 4) usage();
@ -134,11 +137,23 @@ int main(int argc, char **argv)
/* arguments left :
infile outfile relocation offset */
if ((src = fopen(argv[1], "rb")) == NULL)
{
if (UPX && strlen(argv[1]) > 3)
{
strcpy(argv[1] + strlen(argv[1]) - 3, "sys");
if ((src = fopen(argv[1], "rb")) == NULL)
{
printf("Source file %s could not be opened\n", argv[1]);
return 1;
}
compress_sys_file = TRUE;
}
}
if (compress_sys_file) {
fseek(src, 0, SEEK_END);
size = ftell(src);
} else {
if (fread(&header, sizeof(header), 1, src) != 1)
{
printf("Error reading header from %s\n", argv[1]);
@ -151,11 +166,6 @@ int main(int argc, char **argv)
fclose(src);
return 1;
}
if ((dest = fopen(argv[2], "wb+")) == NULL)
{
printf("Destination file %s could not be created\n", argv[2]);
return 1;
}
start_seg = (UWORD)strtol(argv[3], NULL, 0);
if (header.exExtraBytes == 0)
header.exExtraBytes = 0x200;
@ -167,6 +177,7 @@ int main(int argc, char **argv)
printf("image size (less header) = %lu = 0x%lx\n", size, size);
printf("first relocation offset = %u = 0x%u\n", header.exOverlay,
header.exOverlay);
}
/* first read file into memory chunks */
fseek(src, header.exHeaderSize * 16UL, SEEK_SET);
@ -194,6 +205,8 @@ int main(int argc, char **argv)
return 1;
}
}
if (header.exRelocTable && header.exRelocItems)
{
fseek(src, header.exRelocTable, SEEK_SET);
reloc = malloc(header.exRelocItems * sizeof(farptr));
if (reloc == NULL)
@ -207,6 +220,7 @@ int main(int argc, char **argv)
printf("Source file read error\n");
return 1;
}
}
fclose(src);
qsort(reloc, header.exRelocItems, sizeof(reloc[0]), compReloc);
for (i = 0; i < header.exRelocItems; i++)
@ -233,6 +247,17 @@ int main(int argc, char **argv)
*spot1 = segment >> 8;
}
if (flat_exe) {
compress_sys_file = size < 0x10000L;
if (compress_sys_file && strlen(argv[2]) > 3)
strcpy(argv[2] + strlen(argv[2]) - 3, "sys");
}
if ((dest = fopen(argv[2], "wb+")) == NULL)
{
printf("Destination file %s could not be created\n", argv[2]);
return 1;
}
if (UPX)
{
/* UPX HEADER jump $+2+size */
@ -268,7 +293,7 @@ int main(int argc, char **argv)
fwrite(JumpBehindCode, 1, 0x20, dest);
}
if (flat_exe) {
if (flat_exe && !compress_sys_file) {
/* write header without relocations to file */
exe_header nheader = header;
nheader.exRelocItems = 0;
@ -335,8 +360,22 @@ int main(int argc, char **argv)
*(short *)&trailer[1] = (short)size + 0x20;
*(short *)&trailer[23] = header.exInitSS;
*(short *)&trailer[28] = header.exInitSP;
if (compress_sys_file)
/* replace by jmp word ptr [6]: ff 26 06 00
(the .SYS strategy handler which will unpack) */
*(long *)&trailer[30] = 0x000626ffL;
fwrite(trailer, 1, sizeof trailer, dest);
}
if (flat_exe && compress_sys_file) {
/* overwrite first 8 bytes with SYS header */
UWORD dhdr[4];
fseek(dest, 0, SEEK_SET);
for (i = 0; i < 3; i++)
dhdr[i] = 0xffff;
/* strategy will jump to us, interrupt never called */
dhdr[3] = KERNEL_START;
fwrite(dhdr, sizeof(dhdr), 1, dest);
}
fclose(dest);
printf("\nProcessed %d relocations, %d not shown\n",
header.exRelocItems, silentdone);