Initial implementation of src/bank.c

Initial implementation of src/bank.c to act as a sample bank

2 files changed, 111 insertions, 2 deletions

diff --git a/src/Makefile b/src/Makefile
index d5ddc43..b9e9150 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -7,9 +7,9 @@ CC		 = $(CROSS)cc
 CFLAGS		+= -I$(INCLUDE_PATH)
 LDFLAGS		+=
 
-HEADERS		= audio.h riff.h mixer.h synth.h vox.h
+HEADERS		= audio.h riff.h mixer.h synth.h vox.h bank.h
 
-OBJS		= audio.o riff.o mixer.o synth.o vox.o
+OBJS		= audio.o riff.o mixer.o synth.o vox.o bank.o
 
 VERSION_MAJOR	= 0
 VERSION_MINOR	= 0.1
diff --git a/src/bank.c b/src/bank.c
new file mode 100644
index 0000000..8c17bb3
--- /dev/null
+++ b/src/bank.c
@@ -0,0 +1,109 @@
+#include <stdlib.h>
+#include <string.h>
+
+#include <xas/bank.h>
+
+xas_bank *xas_bank_new(size_t sample_size,
+                           size_t sample_rate,
+                           size_t entry_size,
+                           size_t entry_count) {
+    xas_bank *bank;
+
+    size_t entry_size_total = sizeof(xas_bank_entry) + entry_size;
+
+    size_t total = sizeof(xas_bank) + sample_size
+                                      * entry_size_total
+                                      * entry_count;
+
+    if ((bank = malloc(total)) == NULL) {
+        goto error_malloc_bank;
+    }
+
+    memset(bank, '\0', total);
+
+    bank->sample_size = sample_size;
+    bank->sample_rate = sample_rate;
+    bank->entry_size  = entry_size;
+    bank->entry_count = entry_count;
+
+    return bank;
+
+error_malloc_bank:
+    return NULL;
+}
+
+void xas_bank_destroy(xas_bank *bank) {
+    free(bank);
+}
+
+int xas_bank_play(xas_bank *bank, size_t entry, float force) {
+    bank->flags |= XAS_BANK_ACTIVE;
+    bank->force  = force;
+    bank->entry  = entry;
+    bank->index  = 0;
+
+    return 0;
+}
+
+void xas_bank_stop(xas_bank *bank) {
+    bank->flags &= ~XAS_BANK_ACTIVE;
+    bank->force  = 0.0;
+    bank->entry  = 0;
+    bank->index  = 0;
+}
+
+static inline void *ptr(xas_audio_stream *stream, void *buf, size_t index) {
+    return ((uint8_t *)buf) + stream->channels * stream->sample_size * index;
+}
+
+static ssize_t bank_fill(xas_bank *bank,
+                         int16_t *samples,
+                         size_t count,
+                         xas_audio_stream *stream) {
+    size_t index_o = 0,
+           left    = count;
+
+    if (!(bank->flags & XAS_BANK_ACTIVE)) {
+        memset(samples, '\0', count * bank->sample_size);
+
+        return count;
+    }
+
+    while (left) {
+        xas_bank_entry *entry =
+            &((xas_bank_entry *)(bank + 1))[bank->entry];
+
+        size_t remaining = bank->entry_size - bank->index,
+               amount    = remaining < left? remaining: left;
+
+        memcpy(ptr(stream, samples,   index_o),
+               ptr(stream, entry + 1, bank->index),
+               amount * stream->channels * stream->sample_size);
+
+        left    -= amount;
+        index_o += amount;
+
+        bank->index += amount;
+
+        if (bank->index == entry->duration) {
+            bank->index = 0;
+        }
+    }
+
+    return count;
+}
+
+void bank_cleanup(xas_bank *bank,
+                  xas_audio_stream *stream) {
+    return;
+}
+
+xas_audio_stream *xas_bank_stream_new(xas_bank *bank) {
+    return xas_audio_stream_new_source((xas_audio_fill)bank_fill,
+                                         (xas_audio_cleanup)bank_cleanup,
+                                         bank,
+                                         XAS_AUDIO_STREAM_MONO,
+                                         bank->sample_size,
+                                         bank->sample_rate,
+                                         bank->entry_size);
+}