C/C++ Users Group Library 1996 July/C-C++ Users Group Library July 1996.iso/vol_400/424_01/ed_157/do_grep.c

C/C++ Source or Header | 1993-09-10 | 5.0 KB | 158 lines

/*
 * Copyright (C) 1992 by Rush Record ([e-mail])
 *
 * This file is part of ED.
 *
 * ED is free software; you can redistribute it and/or modify it under the terms
 * of the GNU General Public License as published by the Free Software Foundation.
 *
 * ED is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with ED
 * (see the file COPYING).  If not, write to the Free Software Foundation, 675
 * Mass Ave, Cambridge, MA 02139, USA.
 */
#include "opsys.h"

#include <stdio.h>
#include <string.h>

#include "memory.h"
#include "rec.h"
#include "buffer.h"
#include "window.h"
#include "ed_dec.h"
#include "cmd_enum.h"

/******************************************************************************\
|Routine: grep_report_skip
|Callby: do_grep
|Purpose: Reports how many lines did/didn't match.
|Arguments:
|    LINES - the number of lines to report.
|    FUNCTION - either 'skip' or 'match'.
|    BASE - the grep buffer base.
\******************************************************************************/
void grep_report_skip(lines,function,base)
Int lines;
Char *function;
rec_ptr base;
{
    rec_ptr new;
    Char buf[128];
    Int length;

    new = (rec_ptr)imalloc(sizeof(rec_node));
    sprintf(buf,"<%s %d %s>",function,lines,(lines > 1)? "lines" : "line");
    new->data = (Char *)imalloc((length = strlen(buf)) + 1);
    memcpy(new->data,buf,length);
    new->data[length] = '\0';
    new->length = length;
    new->recflags = 1;    /* it is a freeable buffer */
    insq(new,base->prev);
}

/******************************************************************************\
|Routine: grep_report_line
|Callby: do_grep
|Purpose: Puts a matching/non-matching line in the grep record queue.
|Arguments:
|    REC - the record to add to the queue.
|    BASE - the grep buffer base.
\******************************************************************************/
void grep_report_line(rec,base)
rec_ptr rec,base;
{
    rec_ptr new;

    new = (rec_ptr)imalloc(sizeof(rec_node));    /* report contents of line */
    new->data = (Char *)imalloc(rec->length + 1);
    memcpy(new->data,rec->data,new->length = rec->length);
    new->data[rec->length] = '\0';
    new->recflags = 1;    /* it is a freeable buffer */
    insq(new,base->prev);
}

/******************************************************************************\
|Routine: do_grep
|Callby: command
|Purpose: Generates a buffer with grep'd records and spacers.
|Arguments:
|    OLDBASE - the buffer the user is searching for ALL occurrences of the string in.
|    NEWBASE - the buffer that will be created.
|    STRING - the string to search for.
|    GREPPERG - =1 means GREP, =0 means PERG (opposite of GREP).
|    SILENT - flag that <skip...> lines should not appear.
\******************************************************************************/
void do_grep(oldbase,newbase,string,grepperg,silent)
rec_ptr oldbase,newbase;
Int grepperg;
Char *string;
Int silent;
{
    rec_ptr prev,rec,save_prev;
    buf_node search;
    Int byt,lines,hits;
    Char search_flags[5];

/* initialize */
    rec = (save_prev = prev = oldbase)->next;
    byt = 0;
    hits = 0;
/* make an empty buffer to hold the search string */
    search.first = (rec_ptr)&search.first;
    search.last = (rec_ptr)&search.first;
    string_to_buf(string,&search);
/* copy current search flags */
    memcpy(search_flags,SEARCH_FLAGS,((int)NUM_SMODES) >> 1);
    search_flags[1] = 'e';    /* set end mode for search, so we can match first record if it matches the search string at offset 0 */
/* find instances of the search string */
    while(find_string(rec,byt,1,&search,search_flags,1))
    {
        get_string_loc(&rec,&byt);    /* get new location */
        save_prev = prev;
        for(lines = -1;prev != rec;prev = prev->next,lines++);    /* count lines skipped */
        if(lines >= 0)    /* if we're not still on the same record... */
        {
            if(grepperg)
            {
                if(lines > 0 && !silent)    /* if we skipped more than one line forward, report skip */
                    grep_report_skip(lines,"skip",newbase);
                grep_report_line(rec,newbase);
            }
            else
            {
                if(lines > 0)
                {
                    if(hits && !silent)    /* report skip over matching lines */
                        grep_report_skip(hits,"match",newbase);
                    while(lines--)
                        grep_report_line(save_prev = save_prev->next,newbase);
                    hits = 1;
                }
                else
                    hits++;
                save_prev = prev;    /* we have to do this, in case this was the last match in the file. it prevents the code at the end
                                       from reporting the line containing the search string. */
            }
        }
    }
/* report on the tail end of the file */
    if(grepperg)
    {
        for(lines = -1;prev != oldbase;prev = prev->next,lines++);    /* count lines skipped */
        if(lines > 0 && !silent)
            grep_report_skip(lines,"skip",newbase);
    }
    else
    {
        if(hits && !silent)    /* report skip over matching lines */
            grep_report_skip(hits,"match",newbase);
        while((save_prev = save_prev->next) != oldbase)
            grep_report_line(save_prev,newbase);
    }
}