Linux Cubed Series 7: Sunsite/Linux Cubed Series 7 - Sunsite Vol 1.iso/system/admin/linuxcon.000/linuxcon/linuxconf-1.6/misc/fgets.c

C/C++ Source or Header | 1996-03-20 | 4KB | 191 lines

#include <string.h>
#include "misc.h"
#include "../xconf/xconf.h"

/*
    Read a line of a configuration file and process continuation line.
    Return buf, or NULL si eof
    Blank at the end of line are always stripped.
    Everything following comcar is a comment. The line is cut before.
*/
char *fgets_strip (
    char *buf,
    int sizebuf,
    FILE *fin,
    char contcar,        // Continuation char, generally backslash
    char comcar,        // Comment character, generally #
    int *noline,        // This will be updated and contain the line number
                        // Can be NULL
    int *empty)            // Will be != 0 if the line is empty and did not
                        // even hold a comment.
{
    int nocomment = 1;        // No comments found ?
    int contline=0;
    char *debut = buf;
    char *ret = NULL;
    *buf = '\0';
    *empty = 1;
    while (fgets(buf,sizebuf,fin)!=NULL){
        char *end = strip_end (buf);
        char *pt = strchr(buf,comcar);
        if (pt != NULL){
            nocomment = 0;
            *pt = '\0';
            end = strip_end (buf);
        }
        if (noline != NULL) (*noline)++;
        ret = debut;
        if (contline){
            char *pt = str_skip(buf);
            if (pt > buf+1){
                strcpy (buf+1,pt);
                buf[0] = ' ';
                end-=(int)(pt-buf)-1;
            }else if (pt == buf+1){
                buf[0] = ' ';
            }
        }
        if (end > buf && *(end-1) == contcar){
            if (end == buf+1 || *(end-2) != contcar){
                /* Continuation demandé */
                contline = 1;
                end--;
                *end = '\0';
                buf = end;
            }else{
                *(end-1) = '\0';
                break;
            }
        }else{
            break;
        }
    }
    *empty = debut[0] == '\0' && nocomment;
    return ret;
}

/*
    Read a line of a configuration file and process continuation line.
    Return buf, or NULL si eof
    Blank at the end of line are always stripped.
    Everything following comcar is a comment. The line is cut before.
*/
char *fgets_strip (
    char *buf,
    int sizebuf,
    FILE *fin,
    char contcar,        // Continuation char, generally backslash
    char comcar,        // Comment character, generally #
    int *noline)        // This will be updated and contain the line number
                        // Can be NULL
{
    int empty;
    return fgets_strip (buf,sizebuf,fin,contcar,comcar,noline,&empty);
}

/*
    Read a line of a configuration file and process continuation line.
    Return buf, or NULL si eof
    Blank at the end of line are always stripped.
    Everything following comcar is a comment. The line is cut before.

    Continuation character is \
    Comment character is #
*/
char *fgets_strip (
    char *buf,
    int sizebuf,
    FILE *fin,
    int *noline)        // This will be updated and contain the line number
                        // Can be NULL
{
    int empty;
    return fgets_strip (buf,sizebuf,fin,'\\','#',noline,&empty);
}

/*
    Read a line of text and process continuation lines
    unlike fgets_strip, comment are return untouched.

    Return -1 if end of file, 0 if ok
*/
int fgets_cont (char *buf, int size, FILE *fin)
{
    int ret = -1;
    char tmp[500];
    buf[0] = '\0';
    while (fgets(tmp,size,fin) != NULL){
        char sbuf[500];
        str_strip(tmp,sbuf);
        int len = strlen(sbuf);
        strcpy (buf,sbuf);
        buf += len;
        size -= len;
        ret = 0;
        if (len == 0 || sbuf[len-1] != '\\') break;
        *--buf = '\0';
        size++;
    }
    return ret;
}

/*
    Read lines and accumulate comments.
    buf will contain the first non comment, non empty line.
*/
const char *fgets_comments (
    char buf[],
    int size,
    FILE *fin,
    SSTRING &comments)
{
    const char *ret = NULL;
    while (fgets_cont(buf,size,fin)!=-1){
        strip_end (buf);
        char *pt = str_skip (buf);
        if (pt[0] == '\0' || pt[0] == '#'){
            /* #Specification: fgets_comment / strategy
                When parsing comment out of a configuration file, only
                the text is kept (the # is striped). This helps the
                edit process. Comments should be written back with
                comment_write().
            */
            if (pt[0] == '#') pt = str_skip(pt+1);
            strcat (buf,"\n");
            comments.append (pt);
        }else{
            ret = buf;
            break;
        }
    }
    return ret;
}


/*
    Write back a bunch of comment lines
*/
void comment_write (const SSTRING &str, FILE *fout)
{
    const char *pt = str.get();
    while (*pt != '\0'){
        const char *begin = pt;
        pt = strchr(pt,'\n');
        if (pt == begin){
            fputc('\n',fout);
            pt++;
        }else if (pt != NULL){
            char line[1000];
            char *ptl = line;
            while (begin < pt) *ptl++ = *begin++;
            *ptl = '\0';
            fprintf (fout,"# %s\n",line);
            pt++;
        }else{
            fprintf (fout,"# %s\n",begin);
                break;
        }
    }
}