.\"
.\" Bindle Binaries Tools
.\" Copyright (C) 2022 David M. Syzdek <david@syzdek.net>.
.\" All rights reserved.
.\"
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.TH "BINDLE_ARRAY" "3" "@RELEASE_MONTH@" "@PACKAGE_NAME@" "Library Functions Manual"
.SH NAME
bindle_array_dequeue, bindle_array_enqueue, bindle_array_peek - Bindle Binaries Tools queue routines

.SH LIBRARY
Bindle Binaries Tools (libbindle, -lbindle)

.SH SYNOPSIS
.nf
\fB#include\fR \fB<bindle.h>\fR
.sp
.BI "ssize_t bindle_enqueue( void * " obj ", void ** " basep ", size_t * " nelp ","
.BI "           size_t " width ", void * (*" reallocbase ")(void *, size_t) );"
.sp
.BI "void * bindle_dequeue( void * " base ", size_t * " nelp ", size_t  width );"

.SH DESCRIPTION
The \fBbindle_enqueue\fR() and \fBbindle_dequeue\fR() functions implement an
array based queue. The elements in the array are ordered from newest to
oldest with the most recently added element being the first element in the
array and oldest element in the array being the last element. When adding an
element to the queue, all existing elements are shifted by one position within
the array. If \fIreallocbase\fR is NULL, \fBbindle_enqueue\fR() has a cost of
O(n). \fBbindle_dequeue\fR() has a cost of O(1).
.sp
The size (in bytes) of each element of the array is specified by
\fIwidth\fR.
.sp
\fBbindle_enqueue\fR() adds \fIobj\fR to a queue of *\fInelp\fR elements
referenced by \fIbasep\fR. If \fIreallocbase\fR is not NULL,
\fBbindle_enqueue\fR() will attempt to increase the size of the array by
calling \fIreallocbase\fR. If \fIreallocbase\fR is NULL, it is up to the
developer to not queue more elements than can be held by the array. If
successful, the value referenced by \fInelp\fR will be incremented.
.sp
\fBbindle_dequeue\fR() removes and returns the next element in a queue of
*\fInelp\fR elements pointed to by \fIbase\fR.  If successful, the value
referenced by \fInelp\fR will be decremented.

.SH RETURN VALUES
\fBbindle_dequeue\fR() return \fINULL\fR if the queue does not contain any
elements, otherwise a pointer to the next object is returned.
.sp
Upon success, \fBbindle_enqueue\fR() returns 0. If an error ocurred,
\fBbindle_enqueue\fR() returns -1. If \fIreallocbase\fR is NULL,
\fBbindle_enqueue\fR() will always return 0.

.SH EXAMPLE
.nf
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <bindle.h>

struct wc {
    unsigned value;
    char *   name;
} wcs[] = {
    { 0xFFFFFF, "white"   }, { 0xC0C0C0, "silver"  },
    { 0x808080, "gray"    }, { 0x000000, "black"   },
    { 0xFF0000, "red"     }, { 0x800000, "maroon"  }
};

#define nr_wcs (sizeof(wcs) / sizeof(wcs[0]))

int main(void)
{
    size_t      pos, nel, width;
    ssize_t     rc;
    struct wc   **list, *obj, **res;

    nel   = 0;
    list  = NULL;
    width = sizeof(struct wc *);

    for(pos = 0; (pos < nr_wcs); pos++)
    {
        obj = &wcs[pos];
        printf("enqueuing: #%06x %s\\n", obj->value, obj->name);
        rc = bindle_enqueue(&obj, (void **)&list, &nel, width, realloc);
        if (rc == -1)
        {
            fprintf(stderr, "error adding %s to queue\\n", wcs[pos].name);
            free(list);
            exit(EXIT_FAILURE);
        };
    };

    while((res = bindle_dequeue(list, &nel, width)) != NULL)
    {
        printf("dequeued: #%06x %s\\n", (*res)->value, (*res)->name);
    };


    free(list);

    exit(EXIT_SUCCESS);
}
.fi

.SH SEE ALSO
.BR bindle_array (3),
.BR bindle_peek (3)

.SH AUTHOR
David M. Syzdek <david@syzdek.net>

.SH ACKNOWLEDGEMENTS
\fB@PACKAGE_NAME@\fR is developed and maintained by David M. Syzdek
<david@syzdek.net>.

.\" end of man page