ckucmd.c

操作系统源代码

char *cmdv = "Unix cmd package V2(022), 27 Jan 88";
 
/*  C K U C M D  --  Interactive command package for Unix  */

/*
 V2 adds support for Data General and Apollo Aegis.
*/
/*
 Modelled after the DECSYSTEM-20 command parser (the COMND JSYS)
 
 Features:
 . parses and verifies keywords, text strings, numbers, and other data
 . displays appropriate menu or help message when user types "?"
 . does keyword and filename completion when user types ESC
 . accepts any unique abbreviation for a keyword
 . allows keywords to have attributes, like "invisible"
 . can supply defaults for fields omitted by user
 . provides command line editing (character, word, and line deletion)
 . accepts input from keyboard, command files, or redirected stdin
 . allows for full or half duplex operation, character or line input
 . settable prompt, protected from deletion
 
 Functions:
  cmsetp - Set prompt (cmprom is prompt string, cmerrp is error msg prefix)
  cmsavp - Save current prompt
  prompt - Issue prompt 
  cmini  - Clear the command buffer (before parsing a new command)
  cmres  - Reset command buffer pointers (before reparsing)
  cmkey  - Parse a keyword
  cmnum  - Parse a number
  cmifi  - Parse an input file name
  cmofi  - Parse an output file name
  cmfld  - Parse an arbitrary field
  cmtxt  - Parse a text string
  cmcfm  - Parse command confirmation (end of line)
  stripq - Strip out backslash quotes from a string.
 
 Return codes:
  -3: no input provided when required
  -2: input was invalid
  -1: reparse required (user deleted into a preceding field)
   0 or greater: success
  See individual functions for greater detail.
 
 Before using these routines, the caller should #include ckucmd.h, and
 set the program's prompt by calling cmsetp().  If the file parsing
 functions cmifi and cmofi are to be used, this module must be linked
 with a ck?fio file system support module for the appropriate system,
 e.g. ckufio for Unix.  If the caller puts the terminal in
 character wakeup ("cbreak") mode with no echo, then these functions will
 provide line editing -- character, word, and line deletion, as well as
 keyword and filename completion upon ESC and help strings, keyword, or
 file menus upon '?'.  If the caller puts the terminal into character
 wakeup/noecho mode, care should be taken to restore it before exit from
 or interruption of the program.  If the character wakeup mode is not
 set, the system's own line editor may be used.
 
 Author: Frank da Cruz (SY.FDC@CU20B),
 Columbia University Center for Computing Activities, January 1985.
 Copyright (C) 1985, Trustees of Columbia University in the City of New York.
 Permission is granted to any individual or institution to use, copy, or
 redistribute this software so long as it is not sold for profit, provided this
 copyright notice is retained. 
*/

/* Includes */
 
#include <stdio.h>                      /* Standard C I/O package */
#include <ctype.h>                      /* Character types */
#include "ckucmd.h"                     /* Command parsing definitions */
#include "ckcdeb.h"                     /* Formats for debug() */
 
/* Local variables */
 
int psetf = 0,                          /* Flag that prompt has been set */
    cc = 0,                             /* Character count */
    dpx = 0;                            /* Duplex (0 = full) */
 
int hw = HLPLW,                         /* Help line width */
    hc = HLPCW,                         /* Help line column width */
    hh,                                 /* Current help column number */
    hx;                                 /* Current help line position */
 
#define PROML 60                        /* Maximum length for prompt */
 
char cmprom[PROML+1];                   /* Program's prompt */
char *dfprom = "Command? ";             /* Default prompt */
 
char cmerrp[PROML+1];                   /* Program's error message prefix */
 
int cmflgs;                             /* Command flags */
 
char cmdbuf[CMDBL+4];                   /* Command buffer */
char hlpbuf[HLPBL+4];                   /* Help string buffer */
char atmbuf[ATMBL+4];                   /* Atom buffer */
char filbuf[ATMBL+4];                   /* File name buffer */
 
/* Command buffer pointers */
 
static char *bp,                        /* Current command buffer position */
    *pp,                                /* Start of current field */
    *np;                                /* Start of next field */
 
long zchki();                           /* From ck?fio.c. */

 
/*  C M S E T P  --  Set the program prompt.  */
 
cmsetp(s) char *s; {
    char *sx, *sy, *strncpy();
    psetf = 1;                          /* Flag that prompt has been set. */
    strncpy(cmprom,s,PROML - 1);        /* Copy the string. */
    cmprom[PROML] = NUL;                /* Ensure null terminator. */
    sx = cmprom; sy = cmerrp;           /* Also use as error message prefix. */
    while (*sy++ = *sx++) ;             /* Copy. */
    sy -= 2; if (*sy == '>') *sy = NUL; /* Delete any final '>'. */
}
/*  C M S A V P  --  Save a copy of the current prompt.  */
 
cmsavp(s,n) int n; char s[]; {
    extern char *strncpy();                                     /* +1   */
    strncpy(s,cmprom,n-1);
    s[n] = NUL;
}
 
/*  P R O M P T  --  Issue the program prompt.  */
 
prompt() {
    if (psetf == 0) cmsetp(dfprom);     /* If no prompt set, set default. */
    printf("\r%s",cmprom);              /* Print the prompt. */
}
 
 
/*  C M R E S  --  Reset pointers to beginning of command buffer.  */
 
cmres() {  
    cc = 0;                             /* Reset character counter. */
    pp = np = bp = cmdbuf;              /* Point to command buffer. */
    cmflgs = -5;                        /* Parse not yet started. */
}
 
 
/*  C M I N I  --  Clear the command and atom buffers, reset pointers.  */
 
/*
The argument specifies who is to echo the user's typein --
  1 means the cmd package echoes
  0 somebody else (system, front end, terminal) echoes
*/
cmini(d) int d; {
    for (bp = cmdbuf; bp < cmdbuf+CMDBL; bp++) *bp = NUL;
    *atmbuf = NUL;
    dpx = d;
    cmres();
}
 
stripq(s) char *s; {                    /* Function to strip '\' quotes */
    char *t;
    while (*s) {
        if (*s == '\\') {
            for (t = s; *t != '\0'; t++) *t = *(t+1);
        }
        s++;
    }
}

 
/*  C M N U M  --  Parse a number in the indicated radix  */
 
/*  For now, only works for positive numbers in base 10.  */
 
/*
 Returns
   -3 if no input present when required,
   -2 if user typed an illegal number,
   -1 if reparse needed,
    0 otherwise, with n set to number that was parsed
*/
cmnum(xhlp,xdef,radix,n) char *xhlp, *xdef; int radix, *n; {
    int x; char *s;
 
    if (radix != 10) {                  /* Just do base 10 for now */
        printf("cmnum: illegal radix - %d\n",radix);
        return(-1);
    }
 
    x = cmfld(xhlp,xdef,&s);
    debug(F101,"cmnum: cmfld","",x);
    if (x < 0) return(x);    /* Parse a field */
 
    if (digits(atmbuf)) {               /* Convert to number */
        *n = atoi(atmbuf);
        return(x);
    } else {
        printf("\n?not a number - %s\n",s);
        return(-2);     
    }
}

 
/*  C M O F I  --  Parse the name of an output file  */
 
/*
 Depends on the external function zchko(); if zchko() not available, use
 cmfld() to parse output file names.
 
 Returns
   -3 if no input present when required,
   -2 if permission would be denied to create the file,
   -1 if reparse needed,
    0 or 1 otherwise, with xp pointing to name.
*/
cmofi(xhlp,xdef,xp) char *xhlp, *xdef, **xp; {
    int x; char *s;
 
    if (*xhlp == NUL) xhlp = "Output file";
    *xp = "";
 
    if ((x = cmfld(xhlp,xdef,&s)) < 0) return(x);
 
    if (chkwld(s)) {
        printf("\n?Wildcards not allowed - %s\n",s);
        return(-2);
    }
    if (zchko(s) < 0) {
        printf("\n?Write permission denied - %s\n",s);
        return(-2);
    } else {
        *xp = s;
        return(x);
    }
}

 
/*  C M I F I  --  Parse the name of an existing file  */
 
/*
 This function depends on the external functions:
   zchki()  - Check if input file exists and is readable.
   zxpand() - Expand a wild file specification into a list.
   znext()  - Return next file name from list.
 If these functions aren't available, then use cmfld() to parse filenames.
*/
/*
 Returns
   -4 EOF
   -3 if no input present when required,
   -2 if file does not exist or is not readable,
   -1 if reparse needed,
    0 or 1 otherwise, with:
        xp pointing to name,
        wild = 1 if name contains '*' or '?', 0 otherwise.
*/
cmifi(xhlp,xdef,xp,wild) char *xhlp, *xdef, **xp; int *wild; {
    int i, x, xc; long y; char *sp;
 
    cc = xc = 0;                        /* Initialize counts & pointers */
    *xp = "";
    if ((x = cmflgs) != 1) {            /* Already confirmed? */
        x = gtword();                   /* No, get a word */
    } else {
        cc = setatm(xdef);              /* If so, use default, if any. */
    }
    *xp = atmbuf;                       /* Point to result. */
    *wild = chkwld(*xp);
 
    while (1) {
        xc += cc;                       /* Count the characters. */
        debug(F111,"cmifi: gtword",atmbuf,xc);
        switch (x) {
            case -4:                    /* EOF */
            case -2:                    /* Out of space. */
            case -1:                    /* Reparse needed */
                return(x);
 
/* cont'd... */

 
/* ...cmifi(), cont'd */
 
 
            case 0:                     /* SP or NL */
            case 1:
                if (xc == 0) *xp = xdef;    /* If no input, return default. */
                else *xp = atmbuf;
                if (**xp == NUL) return(-3); /* If field empty, return -3. */
                
                /* If filespec is wild, see if there are any matches */
 
                *wild = chkwld(*xp);
                debug(F101," *wild","",*wild);
                if (*wild != 0) {
                    y = zxpand(*xp);
                    if (y == 0) {
                        printf("\n?No files match - %s\n",*xp);
                        return(-2);
                    } else if (y < 0) {
                        printf("\n?Too many files match - %s\n",*xp);
                        return(-2);
                    } else return(x);
                }
 
                /* If not wild, see if it exists and is readable. */
 
                y = zchki(*xp);
                if (y == -3) {
                    printf("\n?Read permission denied - %s\n",*xp);
                    return(-2);
                } else if (y == -2) {
                    printf("\n?File not readable - %s\n",*xp);
                    return(-2);
                } else if (y < 0) {
                    printf("\n?File not found - %s\n",*xp);
                    return(-2);
                }
                return(x);
/* cont'd... */

 
/* ...cmifi(), cont'd */
 
 
            case 2:                     /* ESC */
                if (xc == 0) {
                    if (*xdef != '\0') {
                        printf("%s ",xdef); /* If at beginning of field, */
                        addbuf(xdef);   /* supply default. */
                        cc = setatm(xdef);
                    } else {            /* No default */
                        putchar(BEL);
                    }
                    break;
                } 
                if (*wild = chkwld(*xp)) {  /* No completion if wild */
                    putchar(BEL);
                    break;
                }
                sp = atmbuf + cc;
                *sp++ = '*';
                *sp-- = '\0';
                y = zxpand(atmbuf);     /* Add * and expand list. */
                *sp = '\0';             /* Remove *. */
 
                if (y == 0) {
                    printf("\n?No files match - %s\n",atmbuf);
                    return(-2);
                } else if (y < 0) {
                    printf("\n?Too many files match - %s\n",atmbuf);
                    return(-2);
                } else if (y > 1) {     /* Not unique, just beep. */
                    putchar(BEL);
                } else {                /* Unique, complete it.  */
                    znext(filbuf);      /* Get whole name of file. */
                    sp = filbuf + cc;   /* Point past what user typed. */
                    printf("%s ",sp);   /* Complete the name. */
                    addbuf(sp);         /* Add the characters to cmdbuf. */
                    setatm(pp);         /* And to atmbuf. */
                    *xp = atmbuf;       /* Return pointer to atmbuf. */
                    return(cmflgs = 0);
                }
                break;
 
/* cont'd... */

 
/* ...cmifi(), cont'd */
 
 
            case 3:                     /* Question mark */
                if (*xhlp == NUL)
                    printf(" Input file specification");
                else
                    printf(" %s",xhlp);
                if (xc > 0) {
                    sp = atmbuf + cc;   /* Insert * at end */
#ifdef datageneral
                    *sp++ = '+';        /* Insert +, the DG wild card */