int exec(const char *cmd, char *cmdLine, const unsigned segOfEnv)
{
#ifdef FEATURE_XMS_SWAP
# define buf dosCMDTAIL
# define memcpy _fmemcpy
#else
unsigned char buf[128];
#endif
struct fcb fcb1,
fcb2;
struct ExecBlock execBlock;
int retval;
assert(cmd);
assert(cmdLine);
assert(strlen(cmdLine) <= 125);
invalidateNLSbuf();
/* generate Pascal string from the command line */
memcpy(&buf[1], cmdLine, buf[0] = strlen(cmdLine));
memcpy(&buf[1] + buf[0], "\xd", 2);
/* fill FCBs */
if ((cmdLine = parsfnm(cmdLine, &fcb1, 1)) != 0)
parsfnm(cmdLine, &fcb2, 1);
saveSession();
#ifdef FEATURE_XMS_SWAP
if(XMSisactive() && swapOnExec == TRUE) {
/* Copy the prepared values into the buffers in CSWAP.ASM module */
_fmemcpy(dosFCB1, &fcb1, sizeof(fcb1));
_fmemcpy(dosFCB2, &fcb2, sizeof(fcb1));
assert(strlen(cmd) < 128);
_fstrcpy(dosCMDNAME, cmd);
dosParamDosExec.envSeg = segOfEnv;
retval = XMSexec();
} else
#endif
{
/* fill execute structure */
execBlock.segOfEnv = segOfEnv;
execBlock.cmdLine = (char far *)buf;
execBlock.fcb1 = (struct fcb far *)&fcb1;
execBlock.fcb2 = (struct fcb far *)&fcb2;
retval = lowLevelExec((char far*)cmd, (struct ExecBlock far*)&execBlock);
}
restoreSession();
return decode_exec_result(retval);
}
/* Also: The contents of both buffers is monitored in order to
check if they got overflowed during the MUX call. If so,
the executation is aborted. */
int runExtension(char * const command, char * const line)
{ int clen, llen;
union REGPACK r;
char *p;
int rc = 0; /* Default: is no extension */
assert(command);
assert(line);
assert(strlen(command) < BUFFER_SIZE_MUX_AE);
assert(strlen(line) <= BUFFER_SIZE_MUX_AE);
assert(FP_SEG(command) == FP_SEG(line));
/* Fill the length bytes */
command[-1] = (char)(clen = strlen(command));
line[-1] = (char)(llen = strlen(line));
command[-2] = line[-2] = (char)BUFFER_SIZE_MUX_AE;
/* 4dos v4 compatible space padding */
memset(command + clen, ' ', BUFFER_SIZE_MUX_AE - clen);
/* The command line is \xd terminated, for savety reasons an \0 is
added too */
strcat(line + llen, "\xd");
line[BUFFER_SIZE_MUX_AE] = '\0';
/* Both strings have been prepared now; the MUX call is going to happen */
r.r_ax = 0xae00; /* Installable Commands check for extension */
r.r_dx = 0xffff; /* Magic value */
r.r_cx = -llen; /* length of command line tail (4dos v4) */
r.r_ds = r.r_es = FP_SEG(command);
r.r_bx = FP_OFF(line) - 2;
r.r_si = FP_OFF(command) - 1;
r.r_di = 0; /* Magic value 4dos v4 */
intr(0x2F, &r);
switch(r.r_ax & 0xFF) {
case 0x00: /* No appropriate extension found */
break;
default: /* Invalid response */
dprintf( ("[Invalid response from Installable Commands handler: 0x%02x]\n", r.r_ax & 0xFF) );
break;
case 0xFF: /* Is an extension -> execute the Installable Command */
r.r_ax = 0xae01;
intr(0x2F, &r);
invalidateNLSbuf();
if(command[-1] == 0) /* The command had been processed */
rc = 1; /* Stop interpreting the command */
else rc = 2; /* buffers rewritten */
break;
}
/* Cleanup: Adjust buffers and check for overflow */
if((unsigned char)line[-2] != BUFFER_SIZE_MUX_AE
#if BUFFER_SIZE_MUX_AE < 255
|| (unsigned char)line[-1] > BUFFER_SIZE_MUX_AE
#endif
|| line[BUFFER_SIZE_MUX_AE]) {
/* Yiek! That looks very much like an overflow!! */
dprintf( ("[Memory corrupted during Installable Commands handler]\n") );
longjmp(jmp_beginning, E_CorruptMemory);
}
/* Check command and transform it back into C-style string */
p = command + command[-1];
while(--p >= command && isspace(*p));
p[1] = 0;
/* Check the command line and transform it into a C-style string */
/* Must terminate as line[BUFFER_SIZE] == 0 */
line[(unsigned char)line[-1]]
= line[(unsigned char)line[-2]]
= '\0';
if(0 != (p = strchr(line, '\xd')))
*p = 0;
return rc;
}
