fortune_read

SFL
Version 2.11

`fortune_read`

#include "sflfort.h"
char *
fortune_read (const char *fortune_file)

Synopsis

Reads a random paragraph from the specified fortune file. The fortune file is located in the current directory or on the current path. The paragraph of text is returned in a freshly- allocated block of memory that you should free afterwards using mem_free(). Returns NULL if the fortune file could not be opened.

Source Code - (sflfort.c)

{
    static Bool
        first_time = TRUE;
    FILE
        *fortunes;                      /*  FFF input stream                 */
    byte
        *inbuf,                         /*  Block read from file             */
        *outbuf;                        /*  And after decompression          */
    int
        nbr_blocks,                     /*  Number of blocks in data file    */
        nbr_paras,                      /*  Number of paragraphs in block    */
        paragraph;
    dbyte
        input_dbyte,
        block_size;                     /*  Size of current block            */
    qbyte
        input_qbyte,
        block_offset;                   /*  Offset of block in file          */
    char
        *para_start;                    /*  Start of paragraph               */
    Bool
        compressed;                     /*  Compressed fortune data?         */

    /*  Initialise random-number generator if necessary                      */
    if (first_time)
      {
        randomize ();
        first_time = FALSE;
      }

    /*  Look for fortunes file                                               */
    fortunes = file locate ("PATH", fortune_file, NULL);
    if (fortunes == NULL)
        return (NULL);

    /*  Allocate working buffers                                             */
    inbuf  = mem_alloc (BLOCK_SIZE);
    outbuf = mem_alloc (BLOCK_SIZE);
    if (inbuf == NULL || outbuf == NULL)
      {
        mem_free (inbuf);
        mem_free (outbuf);
        return (NULL);
      }

    /*  Indexed Fortune File format starts with IFFCMP or IFFTXT             */
    file read (fortunes, (char *) inbuf);
    if (memcpy (inbuf, "IFFTXT", 6) == 0)
        compressed = FALSE;
    else
        compressed = TRUE;

    while (fgetc (fortunes) != 26);     /*  Skip past file header            */

    /*  Get total number of blocks in file                                   */
    fread (&input_dbyte, 2, 1, fortunes);
    nbr_blocks = ntohs (input_dbyte);

    /*  Look at random block address in Toc                                  */
    fseek (fortunes, random (nbr_blocks) * 4, SEEK_CUR);
    fread (&input_qbyte, 4, 1, fortunes);
    block_offset = ntohl (input_qbyte);

    /*  Go read, then decompress the block                                   */
    fseek (fortunes, block_offset, SEEK_SET);
    fread (&input_dbyte, 2, 1, fortunes);
    block_size = ntohs (input_dbyte);

    if (compressed)
      {
        fread (inbuf, 1, block_size, fortunes);
        expand block (inbuf, outbuf, block_size);
      }
    else
        fread (outbuf, 1, block_size, fortunes);

    /*  Chose random paragraph from block                                    */
    input_dbyte = *(dbyte *) outbuf;
    nbr_paras   = ntohs (input_dbyte);
    paragraph   = random (nbr_paras);
    para_start  = (char *) outbuf + 2;
    while (paragraph--)
        para_start = strchr (para_start, '\0') + 1;

    para_start = mem_strdup (para_start);

    /*  Release allocated memory                                             */
    fclose (fortunes);
    mem_free (inbuf);
    mem_free (outbuf);

    return (para_start);
}

| << | < | > | >>