diff options
Diffstat (limited to 'sh/input.c')
| -rw-r--r-- | sh/input.c | 531 |
1 files changed, 531 insertions, 0 deletions
diff --git a/sh/input.c b/sh/input.c new file mode 100644 index 0000000..a81fd7b --- /dev/null +++ b/sh/input.c @@ -0,0 +1,531 @@ +/* $NetBSD: input.c,v 1.39 2003/08/07 09:05:32 agc Exp $ */ + +/*- + * Copyright (c) 1991, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Kenneth Almquist. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +#ifndef lint +#if 0 +static char sccsid[] = "@(#)input.c 8.3 (Berkeley) 6/9/95"; +#else +__RCSID("$NetBSD: input.c,v 1.39 2003/08/07 09:05:32 agc Exp $"); +#endif +#endif /* not lint */ + +#include <stdio.h> /* defines BUFSIZ */ +#include <fcntl.h> +#include <errno.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> + +/* + * This file implements the input routines used by the parser. + */ + +#include "shell.h" +#include "redir.h" +#include "syntax.h" +#include "input.h" +#include "output.h" +#include "options.h" +#include "memalloc.h" +#include "error.h" +#include "alias.h" +#include "parser.h" +#include "myhistedit.h" + +#define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ + +MKINIT +struct strpush { + struct strpush *prev; /* preceding string on stack */ + char *prevstring; + int prevnleft; + int prevlleft; + struct alias *ap; /* if push was associated with an alias */ +}; + +/* + * The parsefile structure pointed to by the global variable parsefile + * contains information about the current file being read. + */ + +MKINIT +struct parsefile { + struct parsefile *prev; /* preceding file on stack */ + int linno; /* current line */ + int fd; /* file descriptor (or -1 if string) */ + int nleft; /* number of chars left in this line */ + int lleft; /* number of chars left in this buffer */ + char *nextc; /* next char in buffer */ + char *buf; /* input buffer */ + struct strpush *strpush; /* for pushing strings at this level */ + struct strpush basestrpush; /* so pushing one is fast */ +}; + + +int plinno = 1; /* input line number */ +int parsenleft; /* copy of parsefile->nleft */ +MKINIT int parselleft; /* copy of parsefile->lleft */ +char *parsenextc; /* copy of parsefile->nextc */ +MKINIT struct parsefile basepf; /* top level input file */ +MKINIT char basebuf[BUFSIZ]; /* buffer for top level input file */ +struct parsefile *parsefile = &basepf; /* current input file */ +int init_editline = 0; /* editline library initialized? */ +int whichprompt; /* 1 == PS1, 2 == PS2 */ + +#if WITH_HISTORY +EditLine *el; /* cookie for editline package */ +#endif + +STATIC void pushfile(void); +static int preadfd(void); + +#ifdef mkinit +INCLUDE <stdio.h> +INCLUDE "input.h" +INCLUDE "error.h" + +INIT { + basepf.nextc = basepf.buf = basebuf; +} + +RESET { + if (exception != EXSHELLPROC) + parselleft = parsenleft = 0; /* clear input buffer */ + popallfiles(); +} + +SHELLPROC { + popallfiles(); +} +#endif + + +/* + * Read a line from the script. + */ + +char * +pfgets(char *line, int len) +{ + char *p = line; + int nleft = len; + int c; + + while (--nleft > 0) { + c = pgetc_macro(); + if (c == PEOF) { + if (p == line) + return NULL; + break; + } + *p++ = c; + if (c == '\n') + break; + } + *p = '\0'; + return line; +} + + + +/* + * Read a character from the script, returning PEOF on end of file. + * Nul characters in the input are silently discarded. + */ + +int +pgetc(void) +{ + return pgetc_macro(); +} + + +static int +preadfd(void) +{ + int nr; + char *buf = parsefile->buf; + parsenextc = buf; + +retry: +#ifdef WITH_HISTORY + if (parsefile->fd == 0 && el) { + static const char *rl_cp; + static int el_len; + + if (rl_cp == NULL) + rl_cp = el_gets(el, &el_len); + if (rl_cp == NULL) + nr = 0; + else { + nr = el_len; + if (nr > BUFSIZ - 8) + nr = BUFSIZ - 8; + memcpy(buf, rl_cp, nr); + if (nr != el_len) { + el_len -= nr; + rl_cp += nr; + } else + rl_cp = 0; + } + + } else +#endif + nr = read(parsefile->fd, buf, BUFSIZ - 8); + + + if (nr <= 0) { + if (nr < 0) { + if (errno == EINTR) + goto retry; + if (parsefile->fd == 0 && errno == EWOULDBLOCK) { + int flags = fcntl(0, F_GETFL, 0); + if (flags >= 0 && flags & O_NONBLOCK) { + flags &=~ O_NONBLOCK; + if (fcntl(0, F_SETFL, flags) >= 0) { + out2str("sh: turning off NDELAY mode\n"); + goto retry; + } + } + } + } + nr = -1; + } + return nr; +} + +/* + * Refill the input buffer and return the next input character: + * + * 1) If a string was pushed back on the input, pop it; + * 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading + * from a string so we can't refill the buffer, return EOF. + * 3) If the is more stuff in this buffer, use it else call read to fill it. + * 4) Process input up to the next newline, deleting nul characters. + */ + +int +preadbuffer(void) +{ + char *p, *q; + int more; + int something; + char savec; + + if (parsefile->strpush) { + popstring(); + if (--parsenleft >= 0) + return (*parsenextc++); + } + if (parsenleft == EOF_NLEFT || parsefile->buf == NULL) + return PEOF; + flushout(&output); + flushout(&errout); + +again: + if (parselleft <= 0) { + if ((parselleft = preadfd()) == -1) { + parselleft = parsenleft = EOF_NLEFT; + return PEOF; + } + } + + q = p = parsenextc; + + /* delete nul characters */ + something = 0; + for (more = 1; more;) { + switch (*p) { + case '\0': + p++; /* Skip nul */ + goto check; + + case '\t': + case ' ': + break; + + case '\n': + parsenleft = q - parsenextc; + more = 0; /* Stop processing here */ + break; + + default: + something = 1; + break; + } + + *q++ = *p++; +check: + if (--parselleft <= 0) { + parsenleft = q - parsenextc - 1; + if (parsenleft < 0) + goto again; + *q = '\0'; + more = 0; + } + } + + savec = *q; + *q = '\0'; + +#ifdef WITH_HISTORY + if (parsefile->fd == 0 && hist && something) { + HistEvent he; + INTOFF; + history(hist, &he, whichprompt == 1? H_ENTER : H_APPEND, + parsenextc); + INTON; + } +#endif + + if (vflag) { + out2str(parsenextc); + flushout(out2); + } + + *q = savec; + + return *parsenextc++; +} + +/* + * Undo the last call to pgetc. Only one character may be pushed back. + * PEOF may be pushed back. + */ + +void +pungetc(void) +{ + parsenleft++; + parsenextc--; +} + +/* + * Push a string back onto the input at this current parsefile level. + * We handle aliases this way. + */ +void +pushstring(char *s, int len, void *ap) +{ + struct strpush *sp; + + INTOFF; +/*dprintf("*** calling pushstring: %s, %d\n", s, len);*/ + if (parsefile->strpush) { + sp = ckmalloc(sizeof (struct strpush)); + sp->prev = parsefile->strpush; + parsefile->strpush = sp; + } else + sp = parsefile->strpush = &(parsefile->basestrpush); + sp->prevstring = parsenextc; + sp->prevnleft = parsenleft; + sp->prevlleft = parselleft; + sp->ap = (struct alias *)ap; + if (ap) + ((struct alias *)ap)->flag |= ALIASINUSE; + parsenextc = s; + parsenleft = len; + INTON; +} + +void +popstring(void) +{ + struct strpush *sp = parsefile->strpush; + + INTOFF; + parsenextc = sp->prevstring; + parsenleft = sp->prevnleft; + parselleft = sp->prevlleft; +/*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ + if (sp->ap) + sp->ap->flag &= ~ALIASINUSE; + parsefile->strpush = sp->prev; + if (sp != &(parsefile->basestrpush)) + ckfree(sp); + INTON; +} + +/* + * Set the input to take input from a file. If push is set, push the + * old input onto the stack first. + */ + +void +setinputfile(const char *fname, int push) +{ + int fd; + int fd2; + + INTOFF; + if ((fd = open(fname, O_RDONLY)) < 0) + error("Can't open %s", fname); + if (fd < 10) { + fd2 = copyfd(fd, 10); + close(fd); + if (fd2 < 0) + error("Out of file descriptors"); + fd = fd2; + } + setinputfd(fd, push); + INTON; +} + + +/* + * Like setinputfile, but takes an open file descriptor. Call this with + * interrupts off. + */ + +void +setinputfd(int fd, int push) +{ + (void) fcntl(fd, F_SETFD, FD_CLOEXEC); + if (push) { + pushfile(); + parsefile->buf = ckmalloc(BUFSIZ); + } + if (parsefile->fd > 0) + close(parsefile->fd); + parsefile->fd = fd; + if (parsefile->buf == NULL) + parsefile->buf = ckmalloc(BUFSIZ); + parselleft = parsenleft = 0; + plinno = 1; +} + + +/* + * Like setinputfile, but takes input from a string. + */ + +void +setinputstring(char *string, int push) +{ + INTOFF; + if (push) + pushfile(); + parsenextc = string; + parselleft = parsenleft = strlen(string); + parsefile->buf = NULL; + plinno = 1; + INTON; +} + + + +/* + * To handle the "." command, a stack of input files is used. Pushfile + * adds a new entry to the stack and popfile restores the previous level. + */ + +STATIC void +pushfile(void) +{ + struct parsefile *pf; + + parsefile->nleft = parsenleft; + parsefile->lleft = parselleft; + parsefile->nextc = parsenextc; + parsefile->linno = plinno; + pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile)); + pf->prev = parsefile; + pf->fd = -1; + pf->strpush = NULL; + pf->basestrpush.prev = NULL; + parsefile = pf; +} + + +void +popfile(void) +{ + struct parsefile *pf = parsefile; + + INTOFF; + if (pf->fd >= 0) + close(pf->fd); + if (pf->buf) + ckfree(pf->buf); + while (pf->strpush) + popstring(); + parsefile = pf->prev; + ckfree(pf); + parsenleft = parsefile->nleft; + parselleft = parsefile->lleft; + parsenextc = parsefile->nextc; + plinno = parsefile->linno; + INTON; +} + + +/* + * Return to top level. + */ + +void +popallfiles(void) +{ + while (parsefile != &basepf) + popfile(); +} + + + +/* + * Close the file(s) that the shell is reading commands from. Called + * after a fork is done. + * + * Takes one arg, vfork, which tells it to not modify its global vars + * as it is still running in the parent. + * + * This code is (probably) unnecessary as the 'close on exec' flag is + * set and should be enough. In the vfork case it is definitely wrong + * to close the fds as another fork() may be done later to feed data + * from a 'here' document into a pipe and we don't want to close the + * pipe! + */ + +void +closescript(int vforked) +{ + if (vforked) + return; + popallfiles(); + if (parsefile->fd > 0) { + close(parsefile->fd); + parsefile->fd = 0; + } +} |