3 files changed, 302 insertions, 0 deletions
diff --git a/src/internal/utils/kitbuffer.c b/src/internal/utils/kitbuffer.c
new file mode 100644
index 0000000..0133154
--- /dev/null
+++ b/src/internal/utils/kitbuffer.c
@@ -0,0 +1,100 @@
+#include <stdlib.h>
+#include <assert.h>
+
+#include "kitchensink/internal/utils/kitbuffer.h"
+
+Kit_Buffer* Kit_CreateBuffer(unsigned int size, Kit_BufferFreeCallback free_cb) {
+    Kit_Buffer *b = calloc(1, sizeof(Kit_Buffer));
+    if(b == NULL) {
+        return NULL;
+    }
+    b->size = size;
+    b->free_cb = free_cb;
+    b->data = calloc(size, sizeof(void*));
+    if(b->data == NULL) {
+        free(b);
+        return NULL;
+    }
+    return b;
+}
+
+void Kit_DestroyBuffer(Kit_Buffer *buffer) {
+    if(buffer == NULL) return;
+    Kit_ClearBuffer(buffer);
+    free(buffer->data);
+    free(buffer);
+}
+
+void Kit_ClearBuffer(Kit_Buffer *buffer) {
+    void *data;
+    if(buffer->free_cb == NULL)
+        return;
+    while((data = Kit_ReadBuffer(buffer)) != NULL) {
+        buffer->free_cb(data);
+    }
+}
+
+void* Kit_ReadBuffer(Kit_Buffer *buffer) {
+    assert(buffer != NULL);
+    if(buffer->read_p < buffer->write_p) {
+        void *out = buffer->data[buffer->read_p % buffer->size];
+        buffer->data[buffer->read_p % buffer->size] = NULL;
+        buffer->read_p++;
+        if(buffer->read_p >= buffer->size) {
+            buffer->read_p = buffer->read_p % buffer->size;
+            buffer->write_p = buffer->write_p % buffer->size;
+        }
+        return out;
+    }
+    return NULL;
+}
+
+void* Kit_PeekBuffer(const Kit_Buffer *buffer) {
+    assert(buffer != NULL);
+    if(buffer->read_p < buffer->write_p) {
+        return buffer->data[buffer->read_p % buffer->size];
+    }
+    return NULL;
+}
+
+void Kit_AdvanceBuffer(Kit_Buffer *buffer) {
+    assert(buffer != NULL);
+    if(buffer->read_p < buffer->write_p) {
+        buffer->data[buffer->read_p % buffer->size] = NULL;
+        buffer->read_p++;
+        if(buffer->read_p >= buffer->size) {
+            buffer->read_p = buffer->read_p % buffer->size;
+            buffer->write_p = buffer->write_p % buffer->size;
+        }
+    }
+}
+
+void Kit_ForEachItemInBuffer(const Kit_Buffer *buffer, Kit_ForEachItemCallback cb, void *userdata) {
+    unsigned int read_p = buffer->read_p;
+    unsigned int write_p = buffer->write_p;
+    while(read_p < write_p) {
+        cb(buffer->data[read_p++ % buffer->size], userdata);
+        if(read_p >= buffer->size) {
+            read_p = read_p % buffer->size;
+            write_p = write_p % buffer->size;
+        }
+    }
+}
+
+int Kit_WriteBuffer(Kit_Buffer *buffer, void *ptr) {
+    assert(buffer != NULL);
+    assert(ptr != NULL);
+
+    if(!Kit_IsBufferFull(buffer)) {
+        buffer->data[buffer->write_p % buffer->size] = ptr;
+        buffer->write_p++;
+        return 0;
+    }
+    return 1;
+}
+
+int Kit_IsBufferFull(const Kit_Buffer *buffer) {
+    int len = buffer->write_p - buffer->read_p;
+    int k = (len >= buffer->size);
+    return k;
+}
diff --git a/src/internal/utils/kithelpers.c b/src/internal/utils/kithelpers.c
new file mode 100644
index 0000000..c68f1c7
--- /dev/null
+++ b/src/internal/utils/kithelpers.c
@@ -0,0 +1,30 @@
+#include <libavutil/time.h>
+#include <libavutil/avstring.h>
+
+#include "kitchensink/internal/utils/kithelpers.h"
+
+static const char * const font_mime[] = {
+    "application/x-font-ttf",
+    "application/x-font-truetype",
+    "application/x-truetype-font",
+    "application/x-font-opentype",
+    "application/vnd.ms-opentype",
+    "application/font-sfnt",
+    NULL
+};
+
+double _GetSystemTime() {
+    return (double)av_gettime() / 1000000.0;
+}
+
+bool attachment_is_font(AVStream *stream) {
+    AVDictionaryEntry *tag = av_dict_get(stream->metadata, "mimetype", NULL, AV_DICT_MATCH_CASE);
+    if(tag) {
+        for(int n = 0; font_mime[n]; n++) {
+            if(av_strcasecmp(font_mime[n], tag->value) == 0) {
+                return true;
+            }
+        }
+    }
+    return false;
+}
diff --git a/src/internal/utils/kitringbuffer.c b/src/internal/utils/kitringbuffer.c
new file mode 100644
index 0000000..70fd24f
--- /dev/null
+++ b/src/internal/utils/kitringbuffer.c
@@ -0,0 +1,172 @@
+/*
+ * Ringbuffer
+ *
+ * Copyright (c) 2017, Tuomas Virtanen
+ * license: MIT; see LICENSE for details.
+*/
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <assert.h>
+
+#include "kitchensink/internal/utils/kitringbuffer.h"
+
+/**
+  * Creates a new ringbuffer with the given size.
+  * @param size Size for the new ringbuffer
+  * @return Ringbuffer handle
+  */
+Kit_RingBuffer* Kit_CreateRingBuffer(unsigned int size) {
+    Kit_RingBuffer *rb = calloc(1, sizeof(Kit_RingBuffer));
+    if(rb == NULL) return NULL;
+    rb->size = size;
+    rb->data = malloc(size);
+    if(rb->data == NULL) {
+        free(rb);
+        return NULL;
+    }
+    return rb;
+}
+
+/**
+  * Deletes the given ringbuffer.
+  * @param rb Ringbuffer to be deleted.
+  */
+void Kit_DestroyRingBuffer(Kit_RingBuffer* rb) {
+    if(rb == NULL) return;
+    free(rb->data);
+    free(rb);
+}
+
+/**
+  * Writes to the given ringbuffer. If given length is larger than the amount
+  * the ringbuffer can fit, only the data that fits will be written.
+  * @param rb Ringbuffer to write to.
+  * @param data Data to write
+  * @param len Data length
+  * @return Amount of data that was actually written.
+  */
+int Kit_WriteRingBuffer(Kit_RingBuffer *rb, const char* data, int len) {
+    int k;
+    len = (len > (rb->size - rb->len)) ? (rb->size - rb->len) : len;
+    if(rb->len < rb->size) {
+        if(len + rb->wpos > rb->size) {
+            k = (len + rb->wpos) % rb->size;
+            memcpy((rb->data + rb->wpos), data, len - k);
+            memcpy(rb->data, data+(len-k), k);
+        } else {
+            memcpy((rb->data + rb->wpos), data, len);
+        }
+        rb->len += len;
+        rb->wpos += len;
+        if(rb->wpos >= rb->size) {
+            rb->wpos = rb->wpos % rb->size;
+        }
+        return len;
+    }
+    return 0;
+}
+
+/**
+  * Reads data from ringbuffer. If ringbuffer has less data than was requested,
+  * only the available data will be read.
+  * @param rb Ringbuffer to read from.
+  * @param data Buffer to read into.
+  * @param len How much data do we want
+  * @return Amount of data that was actually read.
+  */
+int Kit_ReadRingBuffer(Kit_RingBuffer *rb, char* data, int len) {
+    int k;
+    len = (len > rb->len) ? rb->len : len;
+    if(rb->len > 0) {
+        if(len + rb->rpos > rb->size) {
+            k = (len + rb->rpos) % rb->size;
+            memcpy(data, (rb->data + rb->rpos), len-k);
+            memcpy(data+(len-k), (rb->data), k);
+        } else {
+            memcpy(data, (rb->data + rb->rpos), len);
+        }
+        rb->len -= len;
+        rb->rpos += len;
+        if(rb->rpos >= rb->size) {
+            rb->rpos = rb->rpos % rb->size;
+        }
+        return len;
+    }
+    return 0;
+}
+
+/**
+  * Peeks into the given ringbuffer. Technically same as rb_read, but does not advance
+  * the internal position pointer. In other words, you may peek as many times as you wish,
+  * and will always get the same data.
+  * @param rb Ringbuffer to peek into.
+  * @param data Buffer to read into
+  * @param len How much data do we need
+  * @return Amount of data actually read
+  */
+int Kit_PeekRingBuffer(const Kit_RingBuffer *rb, char* data, int len) {
+    int k;
+    len = (len > rb->len) ? rb->len : len;
+    if(rb->len > 0) {
+        if(len + rb->rpos > rb->size) {
+            k = (len + rb->rpos) % rb->size;
+            memcpy(data, (rb->data + rb->rpos), len-k);
+            memcpy(data+(len-k), (rb->data), k);
+        } else {
+            memcpy(data, (rb->data + rb->rpos), len);
+        }
+        return len;
+    }
+    return 0;
+}
+
+/**
+  * Advances the internal position counter by given amount. Note that counter can only be
+  * advanced by the amount of unreadable data in ringbuffer.
+  * @param rb Ringbuffer to handle
+  * @param len How much should the position counter be increased
+  * @return How much the position counter was actually increased.
+  */
+int Kit_AdvanceRingBuffer(Kit_RingBuffer *rb, int len) {
+    len = (len > rb->len) ? rb->len : len;
+    if(rb->len > 0) {
+        rb->len -= len;
+        rb->rpos += len;
+        if(rb->rpos >= rb->size) {
+            rb->rpos = rb->rpos % rb->size;
+        }
+        return len;
+    }
+    return 0;
+}
+
+/**
+  * Returns the current length of the Ringbuffer. In other words, how much data
+  * the ringbuffer contains
+  * @param rb Ringbuffer to handle
+  * @return Data in ringbuffer (in bytes).
+  */
+int Kit_GetRingBufferLength(const Kit_RingBuffer *rb) {
+    return rb->len;
+}
+
+/**
+  * Returns the size of the ringbuffer. In other words, the maximum amount of data
+  * the ringbuffer can hold.
+  * @param rb Ringbuffer to handle
+  * @return Size of the ringbuffer
+  */
+int Kit_GetRingBufferSize(const Kit_RingBuffer *rb) {
+    return rb->size;
+}
+
+/**
+  * Returns the free size of the ringbuffer.
+  * @param rb Ringbuffer to handle
+  * @return Free size in the ringbuffer
+  */
+int Kit_GetRingBufferFree(const Kit_RingBuffer *rb) {
+    return rb->size - rb->len;
+}