SuperNET/iguana/databases/cdb-0.75/buffer_put.c

#include "buffer.h"
#include "str.h"
#include "byte.h"
#include "error.h"

static int32_t allwrite(ssize_t (*op)(),int fd,char *buf,unsigned int len)
{
    int32_t w;
    
    while (len)
    {
        w = (int32_t)op(fd,buf,len);
        if ( w == -1 )
        {
            if ( errno == error_intr ) continue;
            return -1; // note that some data may have been written
        }
        if ( w == 0 )
            ; // luser's fault
        buf += w;
        len -= w;
    }
    return 0;
}

int buffer_flush(buffer *s)
{
    int p;
    
    p = s->p;
    if (!p) return 0;
    s->p = 0;
    return allwrite(s->op,s->fd,s->x,p);
}

int buffer_putalign(buffer *s,char *buf,unsigned int len)
{
    unsigned int n;
    
    while (len > (n = s->n - s->p)) {
        byte_copy(s->x + s->p,n,buf); s->p += n; buf += n; len -= n;
        if (buffer_flush(s) == -1) return -1;
    }
    /* now len <= s->n - s->p */
    byte_copy(s->x + s->p,len,buf);
    s->p += len;
    return 0;
}

int buffer_put(buffer *s,char *buf,unsigned int len)
{
    unsigned int n;
    
    n = s->n;
    if (len > n - s->p) {
        if (buffer_flush(s) == -1) return -1;
        /* now s->p == 0 */
        if (n < BUFFER_OUTSIZE) n = BUFFER_OUTSIZE;
        while (len > s->n) {
            if (n > len) n = len;
            if (allwrite(s->op,s->fd,buf,n) == -1) return -1;
            buf += n;
            len -= n;
        }
    }
    /* now len <= s->n - s->p */
    byte_copy(s->x + s->p,len,buf);
    s->p += len;
    return 0;
}

int buffer_putflush(buffer *s,char *buf,unsigned int len)
{
    if (buffer_flush(s) == -1) return -1;
    return allwrite(s->op,s->fd,buf,len);
}

int buffer_putsalign(buffer *s,char *buf)
{
    return buffer_putalign(s,buf,str_len(buf));
}

int buffer_puts(buffer *s,char *buf)
{
    return buffer_put(s,buf,str_len(buf));
}

int buffer_putsflush(buffer *s,char *buf)
{
    return buffer_putflush(s,buf,str_len(buf));
}