Introducing basic objects

The first basic object is extensible buffer.

1 files changed, 189 insertions, 0 deletions

diff --git a/basicobjects/simplebuffer.c b/basicobjects/simplebuffer.c
new file mode 100644
index 0000000..8ddc628
--- /dev/null
+++ b/basicobjects/simplebuffer.c
@@ -0,0 +1,189 @@
+/*
+    Simple buffer
+
+    Basic buffer manipulation routines. Taken from ELAPI code.
+
+    Copyright (C) Dmitri Pal <dpal@redhat.com> 2009 - 2010
+
+    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/>.
+*/
+
+
+#define _GNU_SOURCE
+#include <errno.h>      /* for errors */
+#include <stdlib.h>     /* for free() */
+#include <unistd.h>     /* for write() */
+#include <string.h>     /* for memcpy() */
+
+#include "simplebuffer.h"
+#include "trace.h"
+#include "config.h"
+
+/* End line string */
+#define ENDLNSTR "\n"
+
+/* Function to free buffer */
+void simplebuffer_free(struct simplebuffer *data)
+{
+    TRACE_FLOW_ENTRY();
+
+    if (data) {
+        free(data->buffer);
+        free(data);
+    }
+
+    TRACE_FLOW_EXIT();
+}
+
+/* Allocate buffer structure */
+int simplebuffer_alloc(struct simplebuffer **data)
+{
+    int error = EOK;
+
+    TRACE_FLOW_ENTRY();
+
+    if (!data) {
+        TRACE_ERROR_STRING("Invalid argument", "");
+        error = EINVAL;
+    }
+    else {
+        *data = (struct simplebuffer *)calloc(1,
+                                              sizeof(struct simplebuffer));
+        if (*data == NULL) {
+            TRACE_ERROR_STRING("Failed to allocate memory", "");
+            error = ENOMEM;
+        }
+        else error = EOK;
+    }
+
+    TRACE_FLOW_RETURN(error);
+    return error;
+}
+
+
+/* Grow buffer */
+int simplebuffer_grow(struct simplebuffer *data,
+                      uint32_t len,
+                      uint32_t block)
+{
+    int error = EOK;
+    unsigned char *newbuf = NULL;
+
+    TRACE_FLOW_ENTRY();
+
+    TRACE_INFO_NUMBER("Current length: ", data->length);
+    TRACE_INFO_NUMBER("Current size: ", data->size);
+    TRACE_INFO_NUMBER("Length to have: ", len);
+    TRACE_INFO_NUMBER("Increment length: ", block);
+
+    /* Grow buffer if needed */
+    while (data->length + len >= data->size) {
+        newbuf = realloc(data->buffer, data->size + block);
+        if (newbuf == NULL) {
+            TRACE_ERROR_NUMBER("Error. Failed to allocate memory.", ENOMEM);
+            return ENOMEM;
+        }
+        data->buffer = newbuf;
+        data->size += block;
+        TRACE_INFO_NUMBER("New size: ", data->size);
+    }
+
+    TRACE_INFO_NUMBER("Final size: ", data->size);
+    TRACE_FLOW_RETURN(error);
+    return error;
+}
+
+/* Function to add raw data to the end of the buffer.
+ * Terminating 0 is not counted in length but appended
+ * automatically.
+ */
+int simplebuffer_add_raw(struct simplebuffer *data,
+                         void *data_in,
+                         uint32_t len,
+                         uint32_t block)
+{
+
+    int error = EOK;
+    uint32_t size;
+
+    TRACE_FLOW_ENTRY();
+
+    size = len + 1;
+    error = simplebuffer_grow(data, size,
+                             ((block > size) ? block : size));
+    if (error) {
+        TRACE_ERROR_NUMBER("Failed to grow buffer.", error);
+        return error;
+    }
+
+    memcpy(data->buffer + data->length, data_in, len);
+    data->length += len;
+    data->buffer[data->length] = '\0';
+
+    TRACE_FLOW_EXIT();
+    return error;
+}
+
+/* Finction to add CR to the buffer */
+int simplebuffer_add_cr(struct simplebuffer *data)
+{
+    int error = EOK;
+    char cr[] = ENDLNSTR;
+
+    TRACE_FLOW_ENTRY();
+
+    error = simplebuffer_add_raw(data,
+                                 (void *)cr,
+                                 sizeof(ENDLNSTR) - 1,
+                                 sizeof(ENDLNSTR));
+
+    TRACE_FLOW_RETURN(error);
+    return error;
+}
+
+
+/* Function to write data synchroniusly */
+int simplebuffer_write(int fd, struct simplebuffer *data, uint32_t *left)
+{
+    size_t res;
+    int error;
+
+    TRACE_FLOW_ENTRY();
+
+    /* Write given number of bytes to the socket */
+    res = write(fd,
+                data->buffer + (data->length - *left),
+                (size_t)(*left));
+
+    if (res == -1) {
+        error = errno;
+        TRACE_ERROR_NUMBER("Write failed.", error);
+        return error;
+    }
+
+    (*left) -= res;
+
+    TRACE_FLOW_EXIT();
+    return EOK;
+}
+
+/* Get buffer */
+const unsigned char *simplebuffer_get_buf(struct simplebuffer *data)
+{
+    return data->buffer;
+}
+
+/* Get length */
+uint32_t simplebuffer_get_len(struct simplebuffer *data)
+{
+    return data->length;
+}