Add some more control to the ring buffer.

demo/cat_buffer.c

@@ -42,7 +42,7 @@ void *write_function(void *arg)
     int fd = open(data->path, O_RDONLY);
     if (fd < 0) {
         fprintf(stderr, "Writer thread error: Can't open file");
-        iso_ring_buffer_writer_close(data->rbuf);
+        iso_ring_buffer_writer_close(data->rbuf, 1);
         pthread_exit(NULL);
     }
 
@@ -64,7 +64,7 @@ void *write_function(void *arg)
     fprintf(stderr, "Writer finish: %d\n", res);
 
     close(fd);
-    iso_ring_buffer_writer_close(data->rbuf);
+    iso_ring_buffer_writer_close(data->rbuf, 0);
     pthread_exit(NULL);
 }
 
@@ -88,7 +88,7 @@ void *read_function(void *arg)
     }
     fprintf(stderr, "Reader finish: %d\n", res);
 
-    iso_ring_buffer_reader_close(data->rbuf);
+    iso_ring_buffer_reader_close(data->rbuf, 0);
 
     pthread_exit(NULL);
 }
@@ -105,7 +105,7 @@ int main(int argc, char **argv)
         return 1;
     }
 
-    res = iso_ring_buffer_new(&data.rbuf);
+    res = iso_ring_buffer_new(1024, &data.rbuf);
     if (res < 0) {
         fprintf(stderr, "Can't create buffer\n");
         return 1;

demo/iso.c

@@ -72,7 +72,8 @@ int main(int argc, char **argv)
         NULL, /* output charset */
         0, /* appendable */
         0, /* ms_block */
-        NULL /* overwrite */
+        NULL, /* overwrite */
+        1024 /* fifo_size */
     };
 
     while ((c = getopt(argc, argv, optstring)) != -1) {

demo/iso_grow.c

@@ -55,7 +55,8 @@ int main(int argc, char **argv)
         NULL, /* output charset */
         0, /* appendable */
         0, /* ms_block */
-        NULL /* overwrite */
+        NULL, /* overwrite */
+        1024 /* fifo_size */
     };
     struct iso_read_opts ropts = {
         0, /* block */

demo/iso_modify.c

@@ -50,7 +50,8 @@ int main(int argc, char **argv)
         NULL, /* output charset */
         0, /* appendable */
         0, /* ms_block */
-        NULL /* overwrite */
+        NULL, /* overwrite */
+        1024 /* fifo_size */
     };
     struct iso_read_opts ropts = {
         0, /* block */

demo/iso_ms.c

@@ -50,7 +50,8 @@ int main(int argc, char **argv)
         NULL, /* output charset */
         0, /* appendable */
         0, /* ms_block */
-        NULL /* overwrite */
+        NULL, /* overwrite */
+        1024 /* fifo_size */
     };
     struct iso_read_opts ropts = {
         0, /* block */

src/buffer.c

@@ -18,19 +18,24 @@
 
 #include "buffer.h"
 #include "error.h"
+#include "libburn/libburn.h"
+#include "ecma119.h"
 
 #include <pthread.h>
 #include <string.h>
 
-#define BUFFER_CAPACITY     BLOCK_SIZE * BUFFER_SIZE
-
 #ifndef MIN
 #   define MIN(a, b) (((a) < (b)) ? (a) : (b))
 #endif
 
 struct iso_ring_buffer
 {
-    uint8_t buf[BLOCK_SIZE * BUFFER_SIZE];
+    uint8_t *buf;
+    
+    /*
+     * Max number of bytes in buffer
+     */
+    size_t cap;
 
     /* 
      * Number of bytes available.
@@ -41,9 +46,12 @@ struct iso_ring_buffer
     size_t rpos;
     size_t wpos;
 
-    /* flags to report if read or writer threads ends execution */
+    /* 
-    unsigned int rend :1;
+     * flags to report if read or writer threads ends execution
-    unsigned int wend :1;
+     * 0 not finished, 1 finished ok, 2 finish with error 
+     */
+    unsigned int rend :2; 
+    unsigned int wend :2;
 
     /* just for statistical purposes */
     unsigned int times_full;
@@ -57,12 +65,16 @@ struct iso_ring_buffer
 /**
  * Create a new buffer.
  * 
- * The created buffer can be freed with free(3)
+ * The created buffer should be freed with iso_ring_buffer_free()
  * 
+ * @param size
+ *     Number of blocks in buffer. You should supply a number >= 32, otherwise
+ *     size will be ignored and 32 will be used by default, which leads to a
+ *     64 KiB buffer.
  * @return
  *     1 success, < 0 error
  */
-int iso_ring_buffer_new(IsoRingBuffer **rbuf)
+int iso_ring_buffer_new(size_t size, IsoRingBuffer **rbuf)
 {
     IsoRingBuffer *buffer;
 
@@ -74,7 +86,14 @@ int iso_ring_buffer_new(IsoRingBuffer **rbuf)
     if (buffer == NULL) {
         return ISO_MEM_ERROR;
     }
-
+    
+    buffer->cap = (size > 32 ? size : 32) * BLOCK_SIZE;
+    buffer->buf = malloc(buffer->cap);
+    if (buffer->buf == NULL) {
+        free(buffer);
+        return ISO_MEM_ERROR;
+    }
+    
     buffer->size = 0;
     buffer->wpos = 0;
     buffer->rpos = 0;
@@ -95,6 +114,7 @@ int iso_ring_buffer_new(IsoRingBuffer **rbuf)
 
 void iso_ring_buffer_free(IsoRingBuffer *buf)
 {
+    free(buf->buf);
     pthread_mutex_destroy(&buf->mutex);
     pthread_cond_destroy(&buf->empty);
     pthread_cond_destroy(&buf->full);
@@ -128,11 +148,11 @@ int iso_ring_buffer_write(IsoRingBuffer *buf, uint8_t *data, size_t count)
 
         pthread_mutex_lock(&buf->mutex);
 
-        while (buf->size == BUFFER_CAPACITY) {
+        while (buf->size == buf->cap) {
 
             /*
              * Note. There's only a writer, so we have no race conditions.
-             * Thus, the while(buf->size == BUFFER_CAPACITY) is used here
+             * Thus, the while(buf->size == buf->cap) is used here
              * only to propertly detect the reader has been cancelled
              */
 
@@ -146,12 +166,12 @@ int iso_ring_buffer_write(IsoRingBuffer *buf, uint8_t *data, size_t count)
             pthread_cond_wait(&buf->full, &buf->mutex);
         }
 
-        len = MIN(count - bytes_write, BUFFER_CAPACITY - buf->size);
+        len = MIN(count - bytes_write, buf->cap - buf->size);
-        if (buf->wpos + len > BUFFER_CAPACITY) {
+        if (buf->wpos + len > buf->cap) {
-            len = BUFFER_CAPACITY - buf->wpos;
+            len = buf->cap - buf->wpos;
         }
         memcpy(buf->buf + buf->wpos, data + bytes_write, len);
-        buf->wpos = (buf->wpos + len) % (BUFFER_CAPACITY);
+        buf->wpos = (buf->wpos + len) % (buf->cap);
         bytes_write += len;
         buf->size += len;
 
@@ -202,11 +222,11 @@ int iso_ring_buffer_read(IsoRingBuffer *buf, uint8_t *dest, size_t count)
         }
 
         len = MIN(count - bytes_read, buf->size);
-        if (buf->rpos + len > BUFFER_CAPACITY) {
+        if (buf->rpos + len > buf->cap) {
-            len = BUFFER_CAPACITY - buf->rpos;
+            len = buf->cap - buf->rpos;
         }
         memcpy(dest + bytes_read, buf->buf + buf->rpos, len);
-        buf->rpos = (buf->rpos + len) % (BUFFER_CAPACITY);
+        buf->rpos = (buf->rpos + len) % (buf->cap);
         bytes_read += len;
         buf->size -= len;
 
@@ -217,20 +237,20 @@ int iso_ring_buffer_read(IsoRingBuffer *buf, uint8_t *dest, size_t count)
     return ISO_SUCCESS;
 }
 
-void iso_ring_buffer_writer_close(IsoRingBuffer *buf)
+void iso_ring_buffer_writer_close(IsoRingBuffer *buf, int error)
 {
     pthread_mutex_lock(&buf->mutex);
-    buf->wend = 1;
+    buf->wend = error ? 2 : 1;
 
     /* ensure no reader is waiting */
     pthread_cond_signal(&buf->empty);
     pthread_mutex_unlock(&buf->mutex);
 }
 
-void iso_ring_buffer_reader_close(IsoRingBuffer *buf)
+void iso_ring_buffer_reader_close(IsoRingBuffer *buf, int error)
 {
     pthread_mutex_lock(&buf->mutex);
-    buf->rend = 1;
+    buf->rend = error ? 2 : 1;
 
     /* ensure no writer is waiting */
     pthread_cond_signal(&buf->full);
@@ -252,3 +272,48 @@ unsigned int iso_ring_buffer_get_times_empty(IsoRingBuffer *buf)
 {
     return buf->times_empty;
 }
+
+
+/**
+ * Get the status of the buffer used by a burn_source.
+ * 
+ * @param b
+ *      A burn_source previously obtained with 
+ *      iso_image_create_burn_source().
+ * @param size
+ *      Will be filled with the total size of the buffer, in bytes
+ * @param free_bytes
+ *      Will be filled with the bytes currently available in buffer
+ * @return
+ *      < 0 error, > 0 state:
+ *           1="active"    : input and consumption are active
+ *           2="ending"    : input has ended without error
+ *           3="failing"   : input had error and ended,
+ *           5="abandoned" : consumption has ended prematurely
+ *           6="ended"     : consumption has ended without input error
+ *           7="aborted"   : consumption has ended after input error
+ */
+int iso_ring_buffer_get_status(struct burn_source *b, size_t *size, 
+                               size_t *free_bytes)
+{
+    int ret;
+    IsoRingBuffer *buf;
+    if (b == NULL) {
+        return ISO_NULL_POINTER;
+    }
+    buf = ((Ecma119Image*)(b->data))->buffer;
+    
+    /* get mutex */
+    pthread_mutex_lock(&buf->mutex);
+    if (size) {
+        *size = buf->cap;
+    }
+    if (free_bytes) {
+        *free_bytes = buf->size;
+    }
+
+    ret = (buf->rend + 1) + (buf->wend ? 4 : 0);
+    
+    pthread_mutex_unlock(&buf->mutex);
+    return ret;
+}

src/buffer.h

@@ -12,21 +12,23 @@
 #include <stdlib.h>
 #include <stdint.h>
 
-/* 2 MB buffer */
 #define BLOCK_SIZE          2048
-#define BUFFER_SIZE         1024
 
 typedef struct iso_ring_buffer IsoRingBuffer;
 
 /**
  * Create a new buffer.
  * 
- * The created buffer can be freed with iso_ring_buffer_free(3)
+ * The created buffer should be freed with iso_ring_buffer_free()
  * 
+ * @param size
+ *     Number of blocks in buffer. You should supply a number >= 32, otherwise
+ *     size will be ignored and 32 will be used by default, which leads to a
+ *     64 KiB buffer.
  * @return
  *     1 success, < 0 error
  */
-int iso_ring_buffer_new(IsoRingBuffer **rbuf);
+int iso_ring_buffer_new(size_t size, IsoRingBuffer **rbuf);
 
 /**
  * Free a given buffer
@@ -64,15 +66,21 @@ int iso_ring_buffer_read(IsoRingBuffer *buf, uint8_t *dest, size_t count);
  * Close the buffer (to be called by the writer).
  * You have to explicity close the buffer when you don't have more data to
  * write, otherwise reader will be waiting forever.
+ * 
+ * @param error
+ *     Writer has finished prematurely due to an error
  */
-void iso_ring_buffer_writer_close(IsoRingBuffer *buf);
+void iso_ring_buffer_writer_close(IsoRingBuffer *buf, int error);
 
 /** 
  * Close the buffer (to be called by the reader).
  * If for any reason you don't want to read more data, you need to call this
  * to let the writer thread finish.
+ * 
+ * @param error
+ *     Reader has finished prematurely due to an error
  */
-void iso_ring_buffer_reader_close(IsoRingBuffer *buf);
+void iso_ring_buffer_reader_close(IsoRingBuffer *buf, int error);
 
 /**
  * Get the times the buffer was full.

src/ecma119.c

@@ -808,13 +808,13 @@ void *write_function(void *arg)
         }
     }
 
-    iso_ring_buffer_writer_close(target->buffer);
+    iso_ring_buffer_writer_close(target->buffer, 0);
     pthread_exit(NULL);
 
     write_error: ;
     iso_msg_fatal(target->image->messenger, LIBISO_WRITE_ERROR,
                   "Image write error, code %d", res);
-    iso_ring_buffer_writer_close(target->buffer);
+    iso_ring_buffer_writer_close(target->buffer, 1);
     pthread_exit(NULL);
 }
 
@@ -976,7 +976,7 @@ int ecma119_image_new(IsoImage *src, Ecma119WriteOpts *opts, Ecma119Image **img)
     }
 
     /* create the ring buffer */
-    ret = iso_ring_buffer_new(&target->buffer);
+    ret = iso_ring_buffer_new(opts->fifo_size, &target->buffer);
     if (ret < 0) {
         goto target_cleanup;
     }
@@ -1097,7 +1097,7 @@ static void bs_free_data(struct burn_source *bs)
     Ecma119Image *target = (Ecma119Image*)bs->data;
 
     /* forces writer to stop if it is still running */
-    iso_ring_buffer_reader_close(target->buffer);
+    iso_ring_buffer_reader_close(target->buffer, 0);
 
     /* wait until writer thread finishes */
     pthread_join(target->wthread, NULL);

src/libisofs.h

@@ -196,6 +196,13 @@ typedef struct
      * enought.
      */
     uint8_t *overwrite;
+    
+    /**
+     * Size, in number of blocks, of the FIFO buffer used between the writer
+     * thread and the burn_source. You have to provide at least a 32 blocks
+     * buffer.
+     */
+    size_t fifo_size;
 } Ecma119WriteOpts;
 
 typedef struct Iso_Data_Source IsoDataSource;
@@ -1221,6 +1228,28 @@ void iso_data_source_unref(IsoDataSource *src);
  */
 int iso_data_source_new_from_file(const char *path, IsoDataSource **src);
 
+/**
+ * Get the status of the buffer used by a burn_source.
+ * 
+ * @param b
+ *      A burn_source previously obtained with 
+ *      iso_image_create_burn_source().
+ * @param size
+ *      Will be filled with the total size of the buffer, in bytes
+ * @param free_bytes
+ *      Will be filled with the bytes currently available in buffer
+ * @return
+ *      < 0 error, > 0 state:
+ *           1="active"    : input and consumption are active
+ *           2="ending"    : input has ended without error
+ *           3="failing"   : input had error and ended,
+ *           5="abandoned" : consumption has ended prematurely
+ *           6="ended"     : consumption has ended without input error
+ *           7="aborted"   : consumption has ended after input error
+ */
+int iso_ring_buffer_get_status(struct burn_source *b, size_t *size, 
+                               size_t *free_bytes);
+
 #define ISO_MSGS_MESSAGE_LEN 4096
 
 /**