int
main(void)
{
static char buf[100];
int fd;
// Assumes three file descriptors open.
while((fd = open("console", O_RDWR)) >= 0){
if(fd >= 3){
close(fd);
break;
}
}
// Read and run input commands.
while(getcmd(buf, sizeof(buf)) >= 0){
// add support for built-ins here. cd is a built-in
if(buf[0] == 'c' && buf[1] == 'd' && buf[2] == ' '){
// Clumsy but will have to do for now.
// Chdir has no effect on the parent if run in the child.
buf[strlen(buf)-1] = 0; // chop \n
if(chdir(buf+3) < 0)
printf(2, "cannot cd %s\n", buf+3);
continue;
}
if (buf[0]=='_') { // assume it is a builtin command
dobuiltin(buf);
continue;
}
if(fork1() == 0)
runcmd(parsecmd(buf));
wait();
}
exit();
}
/*
* expand_builtin - evaluate built-in macros.
*/
void
expand_builtin(const char *argv[], int argc, int td)
{
int c, n;
int ac;
static int sysval = 0;
#ifdef DEBUG
printf("argc = %d\n", argc);
for (n = 0; n < argc; n++)
printf("argv[%d] = %s\n", n, argv[n]);
fflush(stdout);
#endif
/*
* if argc == 3 and argv[2] is null, then we
* have macro-or-builtin() type call. We adjust
* argc to avoid further checking..
*/
/* we keep the initial value for those built-ins that differentiate
* between builtin() and builtin.
*/
ac = argc;
if (argc == 3 && !*(argv[2]) && !mimic_gnu)
argc--;
switch (td & TYPEMASK) {
case DEFITYPE:
if (argc > 2)
dodefine(argv[2], (argc > 3) ? argv[3] : null);
break;
case PUSDTYPE:
if (argc > 2)
dopushdef(argv[2], (argc > 3) ? argv[3] : null);
break;
case DUMPTYPE:
dodump(argv, argc);
break;
case TRACEONTYPE:
dotrace(argv, argc, 1);
break;
case TRACEOFFTYPE:
dotrace(argv, argc, 0);
break;
case EXPRTYPE:
/*
* doexpr - evaluate arithmetic
* expression
*/
{
int base = 10;
int maxdigits = 0;
const char *errstr;
if (argc > 3) {
base = strtonum(argv[3], 2, 36, &errstr);
if (errstr) {
m4errx(1, "expr: base %s invalid.", argv[3]);
}
}
if (argc > 4) {
maxdigits = strtonum(argv[4], 0, INT_MAX, &errstr);
if (errstr) {
m4errx(1, "expr: maxdigits %s invalid.", argv[4]);
}
}
if (argc > 2)
pbnumbase(expr(argv[2]), base, maxdigits);
break;
}
case IFELTYPE:
if (argc > 4)
doifelse(argv, argc);
break;
case IFDFTYPE:
/*
* doifdef - select one of two
* alternatives based on the existence of
* another definition
*/
if (argc > 3) {
if (lookup_macro_definition(argv[2]) != NULL)
pbstr(argv[3]);
else if (argc > 4)
pbstr(argv[4]);
}
break;
case LENGTYPE:
/*
* dolen - find the length of the
* argument
*/
pbnum((argc > 2) ? strlen(argv[2]) : 0);
break;
case INCRTYPE:
/*
* doincr - increment the value of the
* argument
*/
if (argc > 2)
pbnum(atoi(argv[2]) + 1);
break;
case DECRTYPE:
/*
* dodecr - decrement the value of the
* argument
*/
if (argc > 2)
pbnum(atoi(argv[2]) - 1);
break;
case SYSCTYPE:
/*
* dosys - execute system command
*/
if (argc > 2) {
fflush(stdout);
sysval = system(argv[2]);
}
break;
case SYSVTYPE:
/*
* dosysval - return value of the last
* system call.
*
*/
pbnum(sysval);
break;
case ESYSCMDTYPE:
if (argc > 2)
doesyscmd(argv[2]);
break;
case INCLTYPE:
if (argc > 2)
if (!doincl(argv[2])) {
if (mimic_gnu) {
warn("%s at line %lu: include(%s)",
CURRENT_NAME, CURRENT_LINE, argv[2]);
exit_code = 1;
} else
err(1, "%s at line %lu: include(%s)",
CURRENT_NAME, CURRENT_LINE, argv[2]);
}
break;
case SINCTYPE:
if (argc > 2)
(void) doincl(argv[2]);
break;
#ifdef EXTENDED
case PASTTYPE:
if (argc > 2)
if (!dopaste(argv[2]))
err(1, "%s at line %lu: paste(%s)",
CURRENT_NAME, CURRENT_LINE, argv[2]);
break;
case SPASTYPE:
if (argc > 2)
(void) dopaste(argv[2]);
break;
case FORMATTYPE:
doformat(argv, argc);
break;
#endif
case CHNQTYPE:
dochq(argv, ac);
break;
case CHNCTYPE:
dochc(argv, argc);
break;
case SUBSTYPE:
/*
* dosub - select substring
*
*/
if (argc > 3)
dosub(argv, argc);
break;
case SHIFTYPE:
/*
* doshift - push back all arguments
* except the first one (i.e. skip
* argv[2])
*/
if (argc > 3) {
for (n = argc - 1; n > 3; n--) {
pbstr(rquote);
pbstr(argv[n]);
pbstr(lquote);
pushback(COMMA);
}
pbstr(rquote);
pbstr(argv[3]);
pbstr(lquote);
}
break;
case DIVRTYPE:
if (argc > 2 && (n = atoi(argv[2])) != 0)
dodiv(n);
else {
active = stdout;
oindex = 0;
}
break;
case UNDVTYPE:
doundiv(argv, argc);
break;
case DIVNTYPE:
/*
* dodivnum - return the number of
* current output diversion
*/
pbnum(oindex);
break;
case UNDFTYPE:
/*
* doundefine - undefine a previously
* defined macro(s) or m4 keyword(s).
*/
if (argc > 2)
for (n = 2; n < argc; n++)
macro_undefine(argv[n]);
break;
case POPDTYPE:
/*
* dopopdef - remove the topmost
* definitions of macro(s) or m4
* keyword(s).
*/
if (argc > 2)
for (n = 2; n < argc; n++)
macro_popdef(argv[n]);
break;
case MKTMTYPE:
/*
* dotemp - create a temporary file
*/
if (argc > 2) {
int fd;
char *temp;
temp = xstrdup(argv[2]);
fd = mkstemp(temp);
if (fd == -1)
err(1,
"%s at line %lu: couldn't make temp file %s",
CURRENT_NAME, CURRENT_LINE, argv[2]);
close(fd);
pbstr(temp);
free(temp);
}
break;
case TRNLTYPE:
/*
* dotranslit - replace all characters in
* the source string that appears in the
* "from" string with the corresponding
* characters in the "to" string.
*/
if (argc > 3) {
char *temp;
temp = xalloc(strlen(argv[2])+1, NULL);
if (argc > 4)
map(temp, argv[2], argv[3], argv[4]);
else
map(temp, argv[2], argv[3], null);
pbstr(temp);
free(temp);
} else if (argc > 2)
pbstr(argv[2]);
break;
case INDXTYPE:
/*
* doindex - find the index of the second
* argument string in the first argument
* string. -1 if not present.
*/
pbnum((argc > 3) ? indx(argv[2], argv[3]) : -1);
break;
case ERRPTYPE:
/*
* doerrp - print the arguments to stderr
* file
*/
if (argc > 2) {
for (n = 2; n < argc; n++)
fprintf(stderr, "%s ", argv[n]);
fprintf(stderr, "\n");
}
break;
case DNLNTYPE:
/*
* dodnl - eat-up-to and including
* newline
*/
while ((c = gpbc()) != '\n' && c != EOF)
;
break;
case M4WRTYPE:
/*
* dom4wrap - set up for
* wrap-up/wind-down activity
*/
if (argc > 2)
dom4wrap(argv[2]);
break;
case EXITTYPE:
/*
* doexit - immediate exit from m4.
*/
killdiv();
exit((argc > 2) ? atoi(argv[2]) : 0);
break;
case DEFNTYPE:
if (argc > 2)
for (n = 2; n < argc; n++)
dodefn(argv[n]);
break;
case INDIRTYPE: /* Indirect call */
if (argc > 2)
doindir(argv, argc);
break;
case BUILTINTYPE: /* Builtins only */
if (argc > 2)
dobuiltin(argv, argc);
break;
case PATSTYPE:
if (argc > 2)
dopatsubst(argv, argc);
break;
case REGEXPTYPE:
if (argc > 2)
doregexp(argv, argc);
break;
case LINETYPE:
doprintlineno(infile+ilevel);
break;
case FILENAMETYPE:
doprintfilename(infile+ilevel);
break;
case SELFTYPE:
pbstr(rquote);
pbstr(argv[1]);
pbstr(lquote);
break;
default:
m4errx(1, "eval: major botch.");
break;
}
}
