/*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * Copyright (c) 1997-2005 * Herbert Xu . 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 /* defines BUFSIZ */ #include #include #include #include /* * This file implements the input routines used by the parser. */ #include "eval.h" #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 "main.h" #ifndef SMALL #include "myhistedit.h" #endif #ifdef HETIO #include "hetio.h" #endif #define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */ #define IBUFSIZ (BUFSIZ + 1) MKINIT struct strpush { struct strpush *prev; /* preceding string on stack */ char *prevstring; int prevnleft; struct alias *ap; /* if push was associated with an alias */ char *string; /* remember the string since it may change */ }; /* * 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[IBUFSIZ]; /* buffer for top level input file */ struct parsefile *parsefile = &basepf; /* current input file */ int whichprompt; /* 1 == PS1, 2 == PS2 */ #ifndef SMALL EditLine *el; /* cookie for editline package */ #endif STATIC void pushfile(void); static int preadfd(void); static void setinputfd(int fd, int push); #ifdef mkinit INCLUDE INCLUDE "input.h" INCLUDE "error.h" INIT { basepf.nextc = basepf.buf = basebuf; } RESET { parselleft = parsenleft = 0; /* clear input buffer */ popallfiles(); } #endif /* * 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(); } /* * Same as pgetc(), but ignores PEOA. */ int pgetc2() { int c; do { c = pgetc_macro(); } while (c == PEOA); return c; } static int preadfd(void) { int nr; char *buf = parsefile->buf; parsenextc = buf; retry: #ifndef SMALL 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 > IBUFSIZ - 1) nr = IBUFSIZ - 1; memcpy(buf, rl_cp, nr); if (nr != el_len) { el_len -= nr; rl_cp += nr; } else rl_cp = 0; } } else #endif #ifdef HETIO nr = hetio_read_input(parsefile->fd); if (nr == -255) #endif nr = read(parsefile->fd, buf, IBUFSIZ - 1); 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; } } } } 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 *q; int more; #ifndef SMALL int something; #endif char savec; while (unlikely(parsefile->strpush)) { if ( parsenleft == -1 && parsefile->strpush->ap && parsenextc[-1] != ' ' && parsenextc[-1] != '\t' ) { return PEOA; } popstring(); if (--parsenleft >= 0) return (signed char)*parsenextc++; } if (unlikely(parsenleft == EOF_NLEFT || parsefile->buf == NULL)) return PEOF; flushout(&output); #ifdef FLUSHERR flushout(&errout); #endif more = parselleft; if (more <= 0) { again: if ((more = preadfd()) <= 0) { parselleft = parsenleft = EOF_NLEFT; return PEOF; } } q = parsenextc; /* delete nul characters */ #ifndef SMALL something = 0; #endif for (;;) { int c; more--; c = *q; if (!c) memmove(q, q + 1, more); else { q++; if (c == '\n') { parsenleft = q - parsenextc - 1; break; } #ifndef SMALL switch (c) { default: something = 1; /* fall through */ case '\t': case ' ': break; } #endif } if (more <= 0) { parsenleft = q - parsenextc - 1; if (parsenleft < 0) goto again; break; } } parselleft = more; savec = *q; *q = '\0'; #ifndef SMALL 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); #ifdef FLUSHERR flushout(out2); #endif } *q = savec; return (signed char)*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, void *ap) { struct strpush *sp; size_t len; len = strlen(s); 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->ap = (struct alias *)ap; if (ap) { ((struct alias *)ap)->flag |= ALIASINUSE; sp->string = s; } parsenextc = s; parsenleft = len; INTON; } void popstring(void) { struct strpush *sp = parsefile->strpush; INTOFF; if (sp->ap) { if (parsenextc[-1] == ' ' || parsenextc[-1] == '\t') { checkkwd |= CHKALIAS; } if (sp->string != sp->ap->val) { ckfree(sp->string); } sp->ap->flag &= ~ALIASINUSE; if (sp->ap->flag & ALIASDEAD) { unalias(sp->ap->name); } } parsenextc = sp->prevstring; parsenleft = sp->prevnleft; /*dprintf("*** calling popstring: restoring to '%s'\n", parsenextc);*/ 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. */ int setinputfile(const char *fname, int flags) { int fd; INTOFF; if ((fd = open(fname, O_RDONLY)) < 0) { if (flags & INPUT_NOFILE_OK) goto out; exitstatus = 127; exerror(EXERROR, "Can't open %s", fname); } if (fd < 10) fd = savefd(fd, fd); setinputfd(fd, flags & INPUT_PUSH_FILE); out: INTON; return fd; } /* * Like setinputfile, but takes an open file descriptor. Call this with * interrupts off. */ static void setinputfd(int fd, int push) { if (push) { pushfile(); parsefile->buf = 0; } parsefile->fd = fd; if (parsefile->buf == NULL) parsefile->buf = ckmalloc(IBUFSIZ); parselleft = parsenleft = 0; plinno = 1; } /* * Like setinputfile, but takes input from a string. */ void setinputstring(char *string) { INTOFF; pushfile(); parsenextc = string; 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. */ void closescript(void) { popallfiles(); if (parsefile->fd > 0) { close(parsefile->fd); parsefile->fd = 0; } }