intrp.c

早期freebsd实现

/* $Id: intrp.c,v 3.0 1992/02/01 03:09:32 davison Trn $
 */
/* This software is Copyright 1991 by Stan Barber. 
 *
 * Permission is hereby granted to copy, reproduce, redistribute or otherwise
 * use this software as long as: there is no monetary profit gained
 * specifically from the use or reproduction of this software, it is not
 * sold, rented, traded or otherwise marketed, and this copyright notice is
 * included prominently in any copy made. 
 *
 * The author make no claims as to the fitness or correctness of this software
 * for any use whatsoever, and it is provided as is. Any use of this software
 * is at the user's own risk. 
 */

#include "EXTERN.h"
#include "common.h"
#include "util.h"
#include "search.h"
#include "cache.h"
#include "bits.h"
#include "head.h"
#include "trn.h"
#include "artsrch.h"
#include "ng.h"
#include "ngdata.h"
#include "respond.h"
#include "rcstuff.h"
#include "artio.h"
#include "init.h"
#include "term.h"
#include "final.h"
#include "rthread.h"
#include "rt-select.h"
#include "nntp.h"
#include "INTERN.h"
#include "intrp.h"

static char * regexp_specials = "^$.*[\\/?%";

char orgname[] = ORGNAME;

#ifdef HAS_UNAME
#include <sys/utsname.h>
struct utsname utsn;
#endif

#ifdef TILDENAME
static char *tildename = Nullch;
static char *tildedir = Nullch;
#endif

#ifdef CONDSUB
char *skipinterp _((char *,char *));
#endif

static void abort_interp _((void));

void
intrp_init(tcbuf)
char *tcbuf;
{
    char *getlogin();
    
    /* get environmental stuff */

#ifdef NEWS_ADMIN
    {
#ifdef HAS_GETPWENT
	struct passwd *getpwnam();
	struct passwd *pwd = getpwnam(NEWS_ADMIN);

	if (pwd != NULL)
	    newsuid = pwd->pw_uid;
#else
#ifdef TILDENAME
	char tildenews[2+sizeof NEWS_ADMIN];
	strcpy(tildenews, "~");
	strcat(tildenews, NEWS_ADMIN);
	(void) filexp(tildenews);
#else
	??? "Define either HAS_GETPWENT or TILDENAME to get NEWS_ADMIN"
#endif  /* TILDENAME */
#endif	/* HAS_GETPWENT */
    }
#endif	/* NEWS_ADMIN */
    /* get home directory */

    homedir = getenv("HOME");
    if (homedir == Nullch)
	homedir = getenv("LOGDIR");

    dotdir = getval("DOTDIR",homedir);

    /* get login name */

    logname = getenv("USER");
    if (logname == Nullch)
	logname = getenv("LOGNAME");
#ifdef GETLOGIN
    if (logname == Nullch)
	logname = savestr(getlogin());
#endif

    spool = savestr(filexp(NEWSSPOOL));	/* usually /usr/spool/news */
    threaddir = filexp(THREAD_DIR);
    if (strEQ(threaddir,spool))
	threaddir = spool;
    else
	threaddir = savestr(threaddir);
    overviewdir = filexp(OVERVIEW_DIR);
    if (strEQ(overviewdir,spool))
	overviewdir = spool;
    else
	overviewdir = savestr(overviewdir);

#ifdef NEWS_ADMIN
    /* if this is the news admin than load his UID into newsuid */

    if ( strEQ(logname,NEWS_ADMIN) )
	newsuid = getuid();
#endif

    if (checkflag)			/* that getwd below takes ~1/3 sec. */
	return;				/* and we do not need it for -c */
    getwd(tcbuf);			/* find working directory name */
    origdir = savestr(tcbuf);		/* and remember it */

    /* get the real name of the person (%N) */
    /* Must be done after logname is read in because BERKNAMES uses that */

    strcpy(tcbuf,getrealname((long)getuid()));
    realname = savestr(tcbuf);

    /* name of header file (%h) */

    headname = savestr(filexp(HEADNAME));

    /* host name that goes in postings (%H) */

    phostname = PHOSTNAME;
    if (*phostname == '/') {
	if ((tmpfp = fopen(phostname,"r")) == NULL) {
	    printf("Warning: Couldn't open %s to determine hostname!\n",
		   phostname); 
	    sig_catcher(0);
	}
	fgets(buf, sizeof(buf), tmpfp);
	if (buf[strlen(buf)-1] == '\n')
	    buf[strlen(buf)-1] = 0;
	fclose(tmpfp);
    }
    else {
#ifdef HAS_GETHOSTNAME
	gethostname(buf,sizeof buf);
#else
# ifdef HAS_UNAME
	/* get sysname */
	uname(&utsn);
	strcpy(buf,utsn.nodename);
# else
#  ifdef PHOSTCMD
       {
	FILE *popen();
	FILE *pipefp = popen(PHOSTCMD,"r");
	
	if (pipefp == Nullfp) {
	    printf("Can't find hostname\n");
	    sig_catcher(0);
	}
	fgets(buf,sizeof buf,pipefp);
	buf[strlen(buf)-1] = '\0';	/* wipe out newline */
	pclose(pipefp);
       }
#  else
	*buf = '\0';
#  endif /* PHOSTCMD */
# endif /* HAS_UNAME */
#endif /* HAS_GETHOSTNAME */
	if (*buf) {
	    char *cp = index(buf,'.');
	    if (cp)
		*cp = '\0';
	    cp = index(phostname,'.');
	    if (cp)
		strcat(buf,cp);
	    phostname = savestr(buf);
	}
    }
}

/* expand filename via %, ~, and $ interpretation */
/* returns pointer to static area */
/* Note that there is a 1-deep cache of ~name interpretation */

char *
filexp(s)
register char *s;
{
    static char filename[CBUFLEN];
    char scrbuf[CBUFLEN];
    register char *d;

#ifdef DEBUG
    if (debug & DEB_FILEXP)
	printf("< %s\n",s) FLUSH;
#endif
    interp(filename, (sizeof filename), s);	
					/* interpret any % escapes */
#ifdef DEBUG
    if (debug & DEB_FILEXP)
	printf("%% %s\n",filename) FLUSH;
#endif
    s = filename;
    if (*s == '~') {	/* does destination start with ~? */
	if (!*(++s) || *s == '/') {
	    sprintf(scrbuf,"%s%s",homedir,s);
				/* swap $HOME for it */
#ifdef DEBUG
    if (debug & DEB_FILEXP)
	printf("~ %s\n",scrbuf) FLUSH;
#endif
	    strcpy(filename,scrbuf);
	}
	else {
#ifdef TILDENAME
	    for (d=scrbuf; isalnum(*s); s++,d++)
		*d = *s;
	    *d = '\0';
	    if (tildedir && strEQ(tildename,scrbuf)) {
		strcpy(scrbuf,tildedir);
		strcat(scrbuf, s);
		strcpy(filename, scrbuf);
#ifdef DEBUG
		if (debug & DEB_FILEXP)
		    printf("r %s %s\n",tildename,tildedir) FLUSH;
#endif
	    }
	    else {
		if (tildename) {
		    free(tildename);
		    free(tildedir);
		}
		tildedir = Nullch;
		tildename = savestr(scrbuf);
#ifdef HAS_GETPWENT	/* getpwnam() is not the paragon of efficiency */
		{
#ifdef notdef
		    struct passwd *getpwnam _((char*));
#endif
		    struct passwd *pwd = getpwnam(tildename);
		    if ( pwd == NULL){
			printf("%s is an unknown user. Using default.\n",tildename) FLUSH;
			return(Nullch);
		    }
		    sprintf(scrbuf,"%s%s",pwd->pw_dir,s);
		    tildedir = savestr(pwd->pw_dir);
		    strcpy(filename,scrbuf);
		    endpwent();
		}
#else			/* this will run faster, and is less D space */
		{	/* just be sure LOGDIRFIELD is correct */
		    FILE *pfp = fopen("/etc/passwd","r");
		    char tmpbuf[512];
		    int i;
		    
		    if (pfp == Nullfp) {
			printf(cantopen,"passwd") FLUSH;
			sig_catcher(0);
		    }
		    while (fgets(tmpbuf,512,pfp) != Nullch) {
			d = cpytill(scrbuf,tmpbuf,':');
#ifdef DEBUG
			if (debug & DEB_FILEXP)
			    printf("p %s\n",tmpbuf) FLUSH;
#endif
			if (strEQ(scrbuf,tildename)) {
			    for (i=LOGDIRFIELD-2; i; i--) {
				if (d)
				    d = index(d+1,':');
			    }
			    if (d) {
				cpytill(scrbuf,d+1,':');
				tildedir = savestr(scrbuf);
				strcat(scrbuf,s);
				strcpy(filename,scrbuf);
			    }
			    break;
			}
		    }
		    fclose(pfp);
		}
#endif
	    }
#else /* !TILDENAME */
#ifdef VERBOSE
	    IF(verbose)
		fputs("~loginname not implemented.\n",stdout) FLUSH;
	    ELSE
#endif
#ifdef TERSE
		fputs("~login not impl.\n",stdout) FLUSH;
#endif
#endif
	}
    }
    else if (*s == '$') {	/* starts with some env variable? */
	d = scrbuf;
	*d++ = '%';
	if (s[1] == '{')
	    strcpy(d,s+2);
	else {
	    *d++ = '{';
	    for (s++; isalnum(*s); s++) *d++ = *s;
				/* skip over token */
	    *d++ = '}';
	    strcpy(d,s);
	}
#ifdef DEBUG
	if (debug & DEB_FILEXP)
	    printf("$ %s\n",scrbuf) FLUSH;
#endif
	interp(filename, (sizeof filename), scrbuf);
					/* this might do some extra '%'s but */
					/* that is how the Mercedes Benz */
    }
#ifdef DEBUG
    if (debug & DEB_FILEXP)
	printf("> %s\n",filename) FLUSH;
#endif
    return filename;
}

#ifdef CONDSUB
/* skip interpolations */

char *
skipinterp(pattern,stoppers)
register char *pattern;
char *stoppers;
{

    while (*pattern && (!stoppers || !index(stoppers,*pattern))) {
#ifdef DEBUG
	if (debug & DEB_INTRP)
	    printf("skipinterp till %s at %s\n",stoppers?stoppers:"",pattern);
#endif
	if (*pattern == '%' && pattern[1]) {
	    switch (*++pattern) {
	    case '{':
		for (pattern++; *pattern && *pattern != '}'; pattern++)
		    if (*pattern == '\\')
			pattern++;
		break;
	    case '[':
		for (pattern++; *pattern && *pattern != ']'; pattern++)
		    if (*pattern == '\\')
			pattern++;
		break;
#ifdef CONDSUB
	    case '(': {
		pattern = skipinterp(pattern+1,"!=");
		if (!*pattern)
		    goto getout;
		for (pattern++; *pattern && *pattern != '?'; pattern++)
		    if (*pattern == '\\')
			pattern++;
		if (!*pattern)
		    goto getout;
		pattern = skipinterp(pattern+1,":)");
		if (*pattern == ':')
		    pattern = skipinterp(pattern+1,")");
		break;
	    }
#endif
#ifdef BACKTICK
	    case '`': {
		pattern = skipinterp(pattern+1,"`");
		break;
	    }
#endif
#ifdef PROMPTTTY
	    case '"':
		pattern = skipinterp(pattern+1,"\"");
		break;
#endif
	    default:
		break;
	    }
	    pattern++;
	}
	else {
	    if (*pattern == '^' && pattern[1])
		pattern += 2;
	    else if (*pattern == '\\' && pattern[1])
		pattern += 2;
	    else
		pattern++;
	}
    }
getout:
    return pattern;			/* where we left off */
}
#endif

/* interpret interpolations */

char *
dointerp(dest,destsize,pattern,stoppers)
register char *dest;
register int destsize;
register char *pattern;
char *stoppers;
{
    char *subj_buf = Nullch;
    char *ngs_buf = Nullch;
    char *refs_buf = Nullch;
    char *artid_buf = Nullch;
    char *reply_buf = Nullch;
    char *from_buf = Nullch;
    char *path_buf = Nullch;
    char *follow_buf = Nullch;
    char *dist_buf = Nullch;
    char *line_buf = Nullch;
    register char *s, *h;
    register int i;
    char scrbuf[512];
    char spfbuf[512];
    bool upper = FALSE;
    bool lastcomp = FALSE;
    bool re_quote = FALSE;
    bool proc_sprintf = FALSE;
    int metabit = 0;

    while (*pattern && (!stoppers || !index(stoppers,*pattern))) {
#ifdef DEBUG
	if (debug & DEB_INTRP)
	    printf("dointerp till %s at %s\n",stoppers?stoppers:"",pattern);
#endif
	if (*pattern == '%' && pattern[1]) {
	    upper = FALSE;
	    lastcomp = FALSE;
	    re_quote = FALSE;
	    proc_sprintf = FALSE;
	    for (s=Nullch; !s; ) {
		switch (*++pattern) {
		case '^':
		    upper = TRUE;
		    break;
		case '_':
		    lastcomp = TRUE;
		    break;
		case '\\':
		    re_quote = TRUE;
		    break;
		case ':':
		    proc_sprintf = TRUE;
		    h = spfbuf;
		    *h++ = '%';
		    pattern++;	/* Skip over ':' */
		    while (*pattern
		     && (*pattern=='.' || *pattern=='-' || isdigit(*pattern))) {
			*h++ = *pattern++;
		    }
		    *h++ = 's';
		    *h++ = '\0';
		    pattern--;
		    break;
		case '/':
#ifdef ARTSRCH
		    s = scrbuf;
		    if (!index("/?g",pattern[-2]))
			*s++ = '/';
		    strcpy(s,lastpat);
		    s += strlen(s);
		    if (pattern[-2] != 'g') {
			if (index("/?",pattern[-2]))
			    *s++ = pattern[-2];
			else
			    *s++ = '/';
			if (art_howmuch == 1)
			    *s++ = 'h';
			else if (art_howmuch == 2)
			    *s++ = 'a';
			if (art_doread)
			    *s++ = 'r';
		    }
		    *s = '\0';
		    s = scrbuf;
#else
		    s = nullstr;
#endif
		    break;
		case '{':
		    pattern = cpytill(scrbuf,pattern+1,'}');
		    if (s = index(scrbuf,'-'))
			*s++ = '\0';
		    else
			s = nullstr;
		    s = getval(scrbuf,s);
		    break;
		case '[':
		    pattern = cpytill(scrbuf,pattern+1,']');
		    i = set_line_type(scrbuf,scrbuf+strlen(scrbuf));
		    if (line_buf)
			free(line_buf);
		    s = line_buf = fetchlines(art,i);
		    break;
#ifdef CONDSUB
		case '(': {
		    COMPEX *oldbra_compex = bra_compex;
		    COMPEX cond_compex;
		    char rch;
		    bool matched;
		    
		    init_compex(&cond_compex);
		    pattern = dointerp(dest,destsize,pattern+1,"!=");
		    rch = *pattern;
		    if (rch == '!')
			pattern++;
		    if (*pattern != '=')
			goto getout;
		    pattern = cpytill(scrbuf,pattern+1,'?');
		    if (!*pattern)
			goto getout;
		    if (s = compile(&cond_compex,scrbuf,TRUE,TRUE)) {
			printf("%s: %s\n",scrbuf,s) FLUSH;
			pattern += strlen(pattern);
			goto getout;
		    }
		    matched = (execute(&cond_compex,dest) != Nullch);
		    if (cond_compex.nbra)	/* were there brackets? */
			bra_compex = &cond_compex;
		    if (matched==(rch == '=')) {
			pattern = dointerp(dest,destsize,pattern+1,":)");
			if (*pattern == ':')
			    pattern = skipinterp(pattern+1,")");
		    }
		    else {
			pattern = skipinterp(pattern+1,":)");
			if (*pattern == ':')
			    pattern++;
			pattern = dointerp(dest,destsize,pattern,")");
		    }
		    s = dest;
		    bra_compex = oldbra_compex;
		    free_compex(&cond_compex);
		    break;
		}
#endif
#ifdef BACKTICK
		case '`': {
		    FILE *pipefp, *popen();

		    pattern = dointerp(scrbuf,(sizeof scrbuf),pattern+1,"`");
		    pipefp = popen(scrbuf,"r");
		    if (pipefp != Nullfp) {
			int len;

			len = fread(scrbuf,sizeof(char),(sizeof scrbuf)-1,
			    pipefp);
			scrbuf[len] = '\0';
			pclose(pipefp);
		    }
		    else {
			printf("\nCan't run %s\n",scrbuf);
			*scrbuf = '\0';
		    }
		    for (s=scrbuf; *s; s++) {
			if (*s == '\n') {
			    if (s[1])
				*s = ' ';
			    else
				*s = '\0';
			}
		    }
		    s = scrbuf;
		    break;
		}
#endif
#ifdef PROMPTTTY
		case '"':
		    pattern = dointerp(scrbuf,(sizeof scrbuf),pattern+1,"\"");
		    fputs(scrbuf,stdout) FLUSH;
		    resetty();
		    gets(scrbuf);
		    noecho();
		    crmode();
		    s = scrbuf;
		    break;
#endif
		case '~':
		    s = homedir;
		    break;
		case '.':
		    s = dotdir;
		    break;
		case '$':
		    s = scrbuf;
		    sprintf(s,"%ld",our_pid);
		    break;
		case '#':