2BSD/src/Mail/lex.c
/* Copyright (c) 1979 Regents of the University of California */
#
#include "rcv.h"
/*
* Mail -- a mail program
*
* Lexical processing of commands.
*/
/*
* Interpret user commands one by one. If standard input is not a tty,
* print no prompt.
*/
commands()
{
int *msgvec, prompt, firstsw, stop(), e;
char linebuf[LINESIZE], word[LINESIZE];
char *arglist[MAXARGC];
struct cmd *com, *quitp;
register char *cp, *cp2;
register int c;
msgvec = (int *) calloc((unsigned) (msgCount + 1), sizeof *msgvec);
if (rcvmode)
if (signal(SIGINT, SIG_IGN) == SIG_DFL)
signal(SIGINT, stop);
input = stdin;
prompt = 1;
if (!intty)
prompt = 0;
firstsw = 1;
quitp = lex("quit");
if (quitp == NONE)
panic("No quit command!?!");
for (;;) {
setexit();
if (firstsw > 0) {
firstsw = 0;
source1(mailrc);
source1(MASTER);
}
/*
* How's this for obscure: after we
* finish sourcing for the first time,
* go off and print the headers!
*/
if (firstsw == 0 && !sourcing) {
firstsw = -1;
if (rcvmode)
announce();
}
/*
* Print the prompt, if needed. Clear out
* string space, and flush the output.
*/
if (!rcvmode && !sourcing)
return;
if (prompt && !sourcing)
printf("_\r");
flush();
sreset();
/*
* Read a line of commands from the current input
* and handle end of file specially.
*/
if (readline(input, linebuf) <= 0) {
if (sourcing) {
unstack();
continue;
}
if (!edit) {
signal(SIGINT, SIG_IGN);
return;
}
edstop();
return;
}
/*
* Strip the white space away from the beginning
* of the command, then scan out a word, which
* consists of anything except digits and white space.
*
* Handle ! escapes differently to get the correct
* lexical conventions.
*/
cp = linebuf;
while (any(*cp, " \t"))
cp++;
if (*cp == '!') {
if (sourcing) {
printf("Can't \"!\" while sourcing\n");
unstack();
continue;
}
shell(cp+1);
continue;
}
cp2 = word;
while (*cp && !any(*cp, " \t0123456789$^.*'\""))
*cp2++ = *cp++;
*cp2 = '\0';
/*
* Look up the command; if not found, bitch.
* Normally, a blank command would map to the
* first command in the table; while sourcing,
* however, we ignore blank lines to eliminate
* confusion.
*/
if (sourcing && equal(word, ""))
continue;
com = lex(word);
if (com == NONE) {
printf("What?\n");
if (sourcing)
unstack();
continue;
}
/*
* Special case so that quit causes a return to
* main, who will call the quit code directly.
* If we are in a source file, just unstack.
*/
if (com == quitp && sourcing) {
unstack();
continue;
}
if (!edit && com == quitp) {
signal(SIGINT, SIG_IGN);
return;
}
/*
* Process the arguments to the command, depending
* on the type he expects. Default to an error.
* If we are sourcing an interactive command, it's
* an error.
*/
if (!rcvmode && (com->c_argtype & M) == 0) {
printf("May not execute \"%s\" while sending\n",
com->c_name);
unstack();
continue;
}
if (sourcing && com->c_argtype & I) {
printf("May not execute \"%s\" while sourcing\n",
com->c_name);
unstack();
continue;
}
e = 1;
switch (com->c_argtype & ~(P|I|M)) {
case MSGLIST:
/*
* A message list defaulting to nearest forward
* legal message.
*/
if ((c = getmsglist(cp, msgvec, com->c_msgflags)) < 0)
break;
if (c == 0) {
*msgvec = first(com->c_msgflags,
com->c_msgmask);
msgvec[1] = NULL;
}
if (*msgvec == NULL) {
printf("No applicable messages\n");
break;
}
e = (*com->c_func)(msgvec);
break;
case NDMLIST:
/*
* A message list with no defaults, but no error
* if none exist.
*/
if (getmsglist(cp, msgvec, com->c_msgflags) < 0)
break;
e = (*com->c_func)(msgvec);
break;
case STRLIST:
/*
* Just the straight string, with
* leading blanks removed.
*/
while (any(*cp, " \t"))
cp++;
e = (*com->c_func)(cp);
break;
case RAWLIST:
/*
* A vector of strings, in shell style.
*/
if ((c = getrawlist(cp, arglist)) < 0)
break;
if (c < com->c_minargs) {
printf("%s requires at least %d arg(s)\n",
com->c_name, com->c_minargs);
break;
}
if (c > com->c_maxargs) {
printf("%s takes no more than %d arg(s)\n",
com->c_name, com->c_maxargs);
break;
}
e = (*com->c_func)(arglist);
break;
case NOLIST:
/*
* Just the constant zero, for exiting,
* eg.
*/
e = (*com->c_func)(0);
break;
default:
panic("Unknown argtype");
}
/*
* Exit the current source file on
* error.
*/
if (e && sourcing)
unstack();
if (com == quitp)
return;
if (value("autoprint") != NOSTR && com->c_argtype & P)
if ((dot->m_flag & MDELETED) == 0)
print(dot);
if (!sourcing)
sawcom = 1;
}
}
/*
* Find the correct command in the command tble corresponding
* to the passed command "word"
*/
struct cmd *
lex(word)
char word[];
{
register struct cmd *cp;
extern struct cmd cmdtab[];
for (cp = &cmdtab[0]; cp->c_name != NOSTR; cp++)
if (isprefix(word, cp->c_name))
return(cp);
return(NONE);
}
/*
* Determine if as1 is a valid prefix of as2.
* Return true if yep.
*/
isprefix(as1, as2)
char *as1, *as2;
{
register char *s1, *s2;
s1 = as1;
s2 = as2;
while (*s1++ == *s2)
if (*s2++ == '\0')
return(1);
return(*--s1 == '\0');
}
/*
* The following gets called on receipt of a rubout. This is
* to abort printout of a command, mainly.
* Dispatching here when command() is inactive crashes rcv.
* Close all open files except 0, 1, 2, and the temporary.
* The special call to getuserid() is needed so it won't get
* annoyed about losing its open file.
* Also, unstack all source files.
*/
stop()
{
register FILE *fp;
signal(SIGINT, SIG_IGN);
while (sourcing)
unstack();
getuserid((char *) -1);
for (fp = &_iob[0]; fp < &_iob[_NFILE]; fp++) {
if (fp == stdin || fp == stdout)
continue;
if (fp == itf || fp == otf)
continue;
if (fp == stderr)
continue;
fclose(fp);
}
clrbuf(stdout);
printf("Interrupt\n");
signal(SIGINT, stop);
reset();
}
/*
* Announce the presence of the current Mail version,
* give the message count, and print a header listing.
*/
char *greeting = "Mail version 1.3 %s. Type ? for help.\n";
announce()
{
char *vec[2];
extern char *version;
vec[0] = "0";
vec[1] = NULL;
if (value("quiet") == NOSTR)
printf(greeting, version);
if (msgCount == 1)
printf("1 message:\n");
else
printf("%d messages:\n", msgCount);
headers(vec);
}
strace() {}
/*
* Print the current version number.
*/
pversion(e)
{
printf(greeting, version);
return(0);
}