From 4930589b97e949a602e82a77463051e0b83d119f Mon Sep 17 00:00:00 2001
From: Fredrik Tolf <fredrik@dolda2000.com>
Date: Mon, 25 Apr 2016 15:06:14 +0200
Subject: [PATCH] lib: Added bufio replacement for stdio.

---
 lib/bufio.c | 302 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/bufio.h |  40 ++++++++
 2 files changed, 342 insertions(+)
 create mode 100644 lib/bufio.c
 create mode 100644 lib/bufio.h

diff --git a/lib/bufio.c b/lib/bufio.c
new file mode 100644
index 0000000..4f2ad10
--- /dev/null
+++ b/lib/bufio.c
@@ -0,0 +1,302 @@
+/*
+    ashd - A Sane HTTP Daemon
+    Copyright (C) 2008  Fredrik Tolf <fredrik@dolda2000.com>
+
+    This program 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, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <utils.h>
+#include <bufio.h>
+
+struct bufio *bioopen(void *pdata, struct bufioops *ops)
+{
+    struct bufio *bio;
+    
+    omalloc(bio);
+    bio->pdata = pdata;
+    bio->ops = ops;
+    bio->bufhint = 4096;
+    return(bio);
+}
+
+int bioclose(struct bufio *bio)
+{
+    int rv;
+    
+    bioflush(bio);
+    if(bio->ops->close)
+	rv = bio->ops->close(bio->pdata);
+    else
+	rv = 0;
+    buffree(bio->rbuf);
+    buffree(bio->wbuf);
+    free(bio);
+    return(rv);
+}
+
+size_t biordata(struct bufio *bio)
+{
+    return(bio->rbuf.d - bio->rh);
+}
+
+size_t biorspace(struct bufio *bio)
+{
+    if((bio->rbuf.d - bio->rh) >= bio->bufhint)
+	return(0);
+    return(bio->bufhint - (bio->rbuf.d - bio->rh));
+}
+
+int bioeof(struct bufio *bio)
+{
+    return(bio->eof && (bio->rh >= bio->rbuf.d));
+}
+
+static ssize_t biofill(struct bufio *bio)
+{
+    size_t ns;
+    ssize_t ret;
+    
+    if(!bio->ops->read) {
+	bio->eof = 1;
+	return(0);
+    }
+    if(bio->eof)
+	return(0);
+    if(bio->rh == bio->rbuf.d)
+	bio->rh = bio->rbuf.d = 0;
+    if(bio->rbuf.d == bio->rbuf.s) {
+	if(bio->rh > 0) {
+	    memmove(bio->rbuf.b, bio->rbuf.b + bio->rh, bio->rbuf.d -= bio->rh);
+	    bio->rh = 0;
+	} else {
+	    if((ns = bio->rbuf.s * 2) < bio->bufhint)
+		ns = bio->bufhint;
+	    sizebuf(bio->rbuf, ns);
+	}
+    }
+    if((bio->rbuf.s > bio->bufhint) && (bio->rbuf.d < bio->bufhint))
+	bio->rbuf.b = srealloc(bio->rbuf.b, bio->rbuf.s = bio->bufhint);
+    ret = bio->ops->read(bio->pdata, bio->rbuf.b + bio->rbuf.d, bio->rbuf.s - bio->rbuf.d);
+    if(ret < 0) {
+	bio->err = errno;
+	return(-1);
+    } else if(ret == 0) {
+	bio->eof = 1;
+	return(0);
+    }
+    bio->rbuf.d += ret;
+    return(bio->rbuf.d - bio->rh);
+}
+
+ssize_t biorensure(struct bufio *bio, size_t bytes)
+{
+    ssize_t ret;
+    
+    while(bio->rbuf.d - bio->rh < bytes) {
+	if((ret = biofill(bio)) <= 0)
+	    return(ret);
+    }
+    return(bio->rbuf.d - bio->rh);
+}
+
+ssize_t biofillsome(struct bufio *bio)
+{
+    return(biofill(bio));
+}
+
+int biogetc(struct bufio *bio)
+{
+    ssize_t ret;
+    
+    while(bio->rbuf.d <= bio->rh) {
+	if((ret = biofill(bio)) <= 0)
+	    return(EOF);
+    }
+    return((unsigned char)bio->rbuf.b[bio->rh++]);
+}
+
+ssize_t bioreadsome(struct bufio *bio, void *buf, size_t len)
+{
+    ssize_t ret;
+    
+    if((bio->rh >= bio->rbuf.d) && ((ret = biofill(bio)) <= 0))
+	return(ret);
+    ret = min(len, bio->rbuf.d - bio->rh);
+    memcpy(buf, bio->rbuf.b + bio->rh, ret);
+    bio->rh += ret;
+    return(ret);
+}
+
+size_t biowdata(struct bufio *bio)
+{
+    return(bio->wbuf.d - bio->wh);
+}
+
+size_t biowspace(struct bufio *bio)
+{
+    if((bio->wbuf.d - bio->wh) >= bio->bufhint)
+	return(0);
+    return(bio->bufhint - (bio->wbuf.d - bio->wh));
+}
+
+int bioflush(struct bufio *bio)
+{
+    ssize_t ret;
+    
+    while(bio->wh < bio->wbuf.d) {
+	ret = bio->ops->write(bio->pdata, bio->wbuf.b + bio->wh, bio->wbuf.d - bio->wh);
+	if(ret < 0) {
+	    bio->err = errno;
+	    return(-1);
+	}
+	bio->wh += ret;
+    }
+    return(0);
+}
+
+int bioflushsome(struct bufio *bio)
+{
+    ssize_t ret;
+    
+    if(bio->wh < bio->wbuf.d) {
+	ret = bio->ops->write(bio->pdata, bio->wbuf.b + bio->wh, bio->wbuf.d - bio->wh);
+	if(ret < 0) {
+	    bio->err = errno;
+	    return(-1);
+	}
+	bio->wh += ret;
+	return(1);
+    } else {
+	return(0);
+    }
+}
+
+ssize_t biowensure(struct bufio *bio, size_t bytes)
+{
+    if(bio->wbuf.s - bio->wbuf.d < bytes) {
+	if(!bio->ops->write) {
+	    errno = bio->err = EPIPE;
+	    return(-1);
+	}
+	if(bioflush(bio) < 0)
+	    return(-1);
+	bio->wh = bio->wbuf.d = 0;
+	if((bio->wbuf.s > bio->bufhint) && (bytes <= bio->bufhint))
+	    bio->wbuf.b = srealloc(bio->wbuf.b, bio->wbuf.s = bio->bufhint);
+	else
+	    sizebuf(bio->wbuf, (bytes < bio->bufhint)?bio->bufhint:bytes);
+    }
+    return(0);
+}
+
+int bioputc(struct bufio *bio, int c)
+{
+    if(biowensure(bio, 1) < 0)
+	return(-1);
+    bio->wbuf.b[bio->wbuf.d++] = c;
+    return(0);
+}
+
+ssize_t biowrite(struct bufio *bio, const void *data, size_t len)
+{
+    ssize_t wb, ret;
+    
+    wb = 0;
+    while(len > 0) {
+	if(biowensure(bio, min(len, bio->bufhint)) < 0) {
+	    if(wb > 0)
+		return(wb);
+	    return(-1);
+	}
+	if(len < bio->wbuf.s - bio->wbuf.d) {
+	    memcpy(bio->wbuf.b + bio->wbuf.d, data, len);
+	    wb += len;
+	    len = 0;
+	} else {
+	    if(bioflush(bio) < 0) {
+		if(wb > 0)
+		    return(wb);
+		return(-1);
+	    }
+	    bio->wh = bio->wbuf.d = 0;
+	    ret = bio->ops->write(bio->pdata, data, len);
+	    if(ret < 0) {
+		if(wb > 0)
+		    return(wb);
+		bio->err = errno;
+		return(-1);
+	    }
+	    data += ret; len -= ret; wb += ret;
+	}
+    }
+    return(0);
+}
+
+ssize_t biowritesome(struct bufio *bio, const void *data, size_t len)
+{
+    ssize_t ret;
+    
+    sizebuf(bio->wbuf, bio->bufhint);
+    if(bio->wh == bio->wbuf.d)
+	bio->wh = bio->wbuf.d = 0;
+    if(bio->wbuf.d == bio->wbuf.s) {
+	if(bio->wh > 0)
+	    memmove(bio->wbuf.b, bio->wbuf.b + bio->wh, bio->wbuf.d -= bio->wh);
+    }
+    ret = min(len, bio->wbuf.s - bio->wbuf.d);
+    memcpy(bio->wbuf.b + bio->wbuf.d, data, ret);
+    bio->wbuf.d += ret;
+    if((bioflushsome(bio) < 0) && (ret == 0))
+	return(-1);
+    return(ret);
+}
+
+int bioprintf(struct bufio *bio, const char *format, ...)
+{
+    va_list args;
+    int ret;
+    
+    if(biowensure(bio, strlen(format)) < 0)
+	return(-1);
+    while(1) {
+	va_start(args, format);
+	ret = vsnprintf(bio->wbuf.b + bio->wbuf.d, bio->wbuf.s - bio->wbuf.d, format, args);
+	va_end(args);
+	if(ret <= bio->wbuf.s - bio->wbuf.d) {
+	    bio->wbuf.d += ret;
+	    return(0);
+	}
+	if(biowensure(bio, ret) < 0)
+	    return(-1);
+    }
+}
+
+ssize_t biocopysome(struct bufio *dst, struct bufio *src)
+{
+    ssize_t ret;
+    
+    if(src->rh >= src->rbuf.d)
+	return(0);
+    if((ret = biowritesome(dst, src->rbuf.b + src->rh, src->rbuf.d - src->rh)) < 0)
+	return(-1);
+    src->rh += ret;
+    return(ret);
+}
diff --git a/lib/bufio.h b/lib/bufio.h
new file mode 100644
index 0000000..7e8b9de
--- /dev/null
+++ b/lib/bufio.h
@@ -0,0 +1,40 @@
+#ifndef _LIB_BUFIO_H
+#define _LIB_BUFIO_H
+
+struct bufioops {
+    ssize_t (*read)(void *pdata, void *buf, size_t len);
+    ssize_t (*write)(void *pdata, const void *buf, size_t len);
+    int (*close)(void *pdata);
+};
+
+struct bufio {
+    struct charbuf rbuf, wbuf;
+    size_t rh, wh, bufhint;
+    int err, eof;
+    void *pdata;
+    struct bufioops *ops;
+};
+
+struct bufio *bioopen(void *pdata, struct bufioops *ops);
+int bioclose(struct bufio *bio);
+
+size_t biordata(struct bufio *bio);
+size_t biorspace(struct bufio *bio);
+int bioeof(struct bufio *bio);
+ssize_t biorensure(struct bufio *bio, size_t bytes);
+ssize_t biofillsome(struct bufio *bio);
+int biogetc(struct bufio *bio);
+ssize_t bioreadsome(struct bufio *bio, void *buf, size_t len);
+
+size_t biowdata(struct bufio *bio);
+size_t biowspace(struct bufio *bio);
+int bioflush(struct bufio *bio);
+int bioflushsome(struct bufio *bio);
+ssize_t biowensure(struct bufio *bio, size_t bytes);
+int bioputc(struct bufio *bio, int c);
+ssize_t biowrite(struct bufio *bio, const void *data, size_t len);
+ssize_t biowritesome(struct bufio *bio, const void *data, size_t len);
+int bioprintf(struct bufio *bio, const char *format, ...);
+ssize_t biocopysome(struct bufio *dst, struct bufio *src);
+
+#endif
-- 
2.11.0