SvarDOSSvarDOS Packages

BlueGreycalmElegant

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• This comparison shows the changes necessary to convert path

  → /svarcom/trunk/command.c @ 489

  → /svarcom/trunk/command.c @ 490

  ↔ Reverse comparison

• Compare Path:	Rev

  With Path:	Rev

Ignore whitespace Rev 489 → Rev 490

/svarcom/trunk/command.c
87,7 → 87,47
unsigned short envsiz;
};
/* max length of the cmdline storage (bytes) - includes also max length of
* line loaded from a BAT file (no more than 255 bytes!) */
#define CMDLINE_MAXLEN 255
/* sets guard values at a few places in memory for later detection of
* overflows via memguard_check() */
static void memguard_set(void) {
BUFFER[sizeof(BUFFER) - 1] = 0xC7;
BUFFER[sizeof(BUFFER) - (CMDLINE_MAXLEN + 3)] = 0xC7;
}
/* checks for valguards at specific memory locations, returns 0 on success */
static int memguard_check(unsigned short rmodseg) {
/* check RMOD signature (would be overwritten in case of stack overflow */
static char msg[] = "!! MEMORY CORRUPTION ## DETECTED !!";
unsigned short far *rmodsig = MK_FP(rmodseg, 0x100 + 6);
if (*rmodsig != 0x2019) {
msg[22] = '1';
outputnl(msg);
printf("rmodseg = %04X ; *rmodsig = %04X\r\n", rmodseg, *rmodsig);
return(1);
}
/* check last BUFFER byte (could be overwritten by cmdline) */
if (BUFFER[sizeof(BUFFER) - 1] != 0xC7) {
msg[22] = '2';
outputnl(msg);
return(2);
}
/* check that cmdline BUFFER's end hasn't been touched by something else */
if (BUFFER[sizeof(BUFFER) - (CMDLINE_MAXLEN + 3)] != 0xC7) {
msg[22] = '3';
outputnl(msg);
return(3);
}
/* all good */
return(0);
}
/* parses command line the hard way (directly from PSP) */
static void parse_argv(struct config *cfg) {
unsigned short i;
607,10 → 647,6
}
/* max length of the cmdline storage (bytes) - includes also max length of
* line loaded from a BAT file (no more than 255 bytes!) */
#define CMDLINE_MAXLEN 255
int main(void) {
static struct config cfg;
static unsigned short far *rmod_envseg;
638,6 → 674,9
if (rmod->flags & FLAG_EXEC_AND_QUIT) sayonara(rmod);
}
/* install a few guardvals in memory to detect some cases of overflows */
memguard_set();
rmod_envseg = MK_FP(rmod->rmodseg, RMOD_OFFSET_ENVSEG);
lastexitcode = MK_FP(rmod->rmodseg, RMOD_OFFSET_LEXITCODE);
666,9 → 705,13
/* cancel any redirections that may have been set up before */
redir_revert();
/* preset cmdline to point at the end of my general-purpose buffer */
cmdline = BUFFER + sizeof(BUFFER) - (CMDLINE_MAXLEN + 1);
/* memory check */
memguard_check(rmod->rmodseg);
/* preset cmdline to point at the end of my general-purpose buffer (with
* one extra byte for the NULL terminator and another for memguard val) */
cmdline = BUFFER + sizeof(BUFFER) - (CMDLINE_MAXLEN + 2);
/* (re)load translation strings if needed */
nls_langreload(BUFFER, *rmod_envseg);