input: Introduce new input module API.

This is a work in progress.

Makefile.am

@@ -42,12 +42,12 @@ libsigrok_la_SOURCES = \
 	src/std.c
 
 # Input modules
+#	src/input/binary.c \
+#	src/input/chronovu_la8.c \
+#	src/input/csv.c \
+#	src/input/vcd.c
 libsigrok_la_SOURCES += \
-	src/input/binary.c \
-	src/input/chronovu_la8.c \
-	src/input/csv.c \
 	src/input/input.c \
-	src/input/vcd.c \
 	src/input/wav.c
 
 # Output modules

include/libsigrok/libsigrok.h

@@ -443,6 +443,21 @@ struct sr_option {
 	GSList *values;
 };
 
+/** Input module metadata keys. */
+enum sr_input_meta_keys {
+	/** The input filename, if there is one. */
+	SR_INPUT_META_FILENAME = 0x01,
+	/** The input file's size in bytes. */
+	SR_INPUT_META_FILESIZE = 0x02,
+	/** The first 128 bytes of the file, provided as a GString. */
+	SR_INPUT_META_HEADER = 0x04,
+	/** The file's MIME type. */
+	SR_INPUT_META_MIMETYPE = 0x08,
+
+	/** The module cannot identify a file without this metadata. */
+	SR_INPUT_META_REQUIRED = 0x80,
+};
+
 struct sr_input;
 struct sr_input_module;
 struct sr_output;

include/libsigrok/proto.h

@@ -124,7 +124,20 @@ SR_API int sr_session_source_remove_channel(struct sr_session *session,
 
 /*--- input/input.c ---------------------------------------------------------*/
 
-SR_API struct sr_input_module **sr_input_list(void);
+SR_API const struct sr_input_module **sr_input_list(void);
+SR_API const char *sr_input_id_get(const struct sr_input_module *in);
+SR_API const char *sr_input_name_get(const struct sr_input_module *in);
+SR_API const char *sr_input_description_get(const struct sr_input_module *in);
+SR_API const struct sr_input_module *sr_input_find(char *id);
+SR_API const struct sr_option *sr_input_options_get(const struct sr_input_module *in);
+SR_API void sr_input_options_free(const struct sr_input_module *in);
+SR_API struct sr_input *sr_input_new(const struct sr_input_module *imod,
+		GHashTable *options);
+SR_API const struct sr_input *sr_input_scan_buffer(GString *buf);
+SR_API const struct sr_input *sr_input_scan_file(const char *filename);
+SR_API struct sr_dev_inst *sr_input_dev_inst_get(const struct sr_input *in);
+SR_API int sr_input_send(const struct sr_input *in, GString *buf);
+SR_API int sr_input_free(const struct sr_input *in);
 
 /*--- output/output.c -------------------------------------------------------*/
 

src/backend.c

@@ -215,7 +215,7 @@ static int sanity_check_all_drivers(void)
 static int sanity_check_all_input_modules(void)
 {
 	int i, errors, ret = SR_OK;
-	struct sr_input_module **inputs;
+	const struct sr_input_module **inputs;
 	const char *d;
 
 	sr_spew("Sanity-checking all input modules.");
@@ -230,7 +230,11 @@ static int sanity_check_all_input_modules(void)
 			sr_err("No ID in module %d ('%s').", i, d);
 			errors++;
 		}
-		if (!inputs[i]->description) {
+		if (!inputs[i]->name) {
+			sr_err("No name in module %d ('%s').", i, d);
+			errors++;
+		}
+		if (!inputs[i]->desc) {
 			sr_err("No description in module %d ('%s').", i, d);
 			errors++;
 		}
@@ -242,8 +246,8 @@ static int sanity_check_all_input_modules(void)
 			sr_err("No init in module %d ('%s').", i, d);
 			errors++;
 		}
-		if (!inputs[i]->loadfile) {
+		if (!inputs[i]->receive) {
-			sr_err("No loadfile in module %d ('%s').", i, d);
+			sr_err("No receive in module %d ('%s').", i, d);
 			errors++;
 		}
 

src/input/binary.c

@@ -144,7 +144,7 @@ static int loadfile(struct sr_input *in, const char *filename)
 
 SR_PRIV struct sr_input_module input_binary = {
 	.id = "binary",
-	.description = "Raw binary",
+	.desc = "Raw binary",
 	.format_match = format_match,
 	.init = init,
 	.loadfile = loadfile,

src/input/chronovu_la8.c

@@ -199,7 +199,7 @@ static int loadfile(struct sr_input *in, const char *filename)
 
 SR_PRIV struct sr_input_module input_chronovu_la8 = {
 	.id = "chronovu-la8",
-	.description = "ChronoVu LA8",
+	.desc = "ChronoVu LA8",
 	.format_match = format_match,
 	.init = init,
 	.loadfile = loadfile,

src/input/csv.c

@@ -865,7 +865,7 @@ static int loadfile(struct sr_input *in, const char *filename)
 
 SR_PRIV struct sr_input_module input_csv = {
 	.id = "csv",
-	.description = "Comma-separated values (CSV)",
+	.desc = "Comma-separated values (CSV)",
 	.format_match = format_match,
 	.init = init,
 	.loadfile = loadfile,

src/input/input.c

@@ -1,7 +1,7 @@
 /*
  * This file is part of the libsigrok project.
  *
- * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
+ * Copyright (C) 2014 Bert Vermeulen <bert@biot.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
@@ -17,9 +17,17 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
 #include "libsigrok.h"
 #include "libsigrok-internal.h"
 
+#define LOG_PREFIX "input"
+
 /**
  * @file
  *
@@ -57,20 +65,427 @@ extern SR_PRIV struct sr_input_module input_vcd;
 extern SR_PRIV struct sr_input_module input_wav;
 /* @endcond */
 
-static struct sr_input_module *input_module_list[] = {
+static const struct sr_input_module *input_module_list[] = {
-	&input_vcd,
+//	&input_vcd,
-	&input_chronovu_la8,
+//	&input_chronovu_la8,
 	&input_wav,
-	&input_csv,
+//	&input_csv,
 	/* This one has to be last, because it will take any input. */
-	&input_binary,
+//	&input_binary,
 	NULL,
 };
 
-/** @since 0.1.0 */
+/** @since 0.4.0 */
-SR_API struct sr_input_module **sr_input_list(void)
+SR_API const struct sr_input_module **sr_input_list(void)
 {
 	return input_module_list;
 }
 
+/**
+ * Returns the specified input module's ID.
+ *
+ * @since 0.4.0
+ */
+SR_API const char *sr_input_id_get(const struct sr_input_module *o)
+{
+	if (!o) {
+		sr_err("Invalid input module NULL!");
+		return NULL;
+	}
+
+	return o->id;
+}
+
+/**
+ * Returns the specified input module's name.
+ *
+ * @since 0.4.0
+ */
+SR_API const char *sr_input_name_get(const struct sr_input_module *o)
+{
+	if (!o) {
+		sr_err("Invalid input module NULL!");
+		return NULL;
+	}
+
+	return o->name;
+}
+
+/**
+ * Returns the specified input module's description.
+ *
+ * @since 0.4.0
+ */
+SR_API const char *sr_input_description_get(const struct sr_input_module *o)
+{
+	if (!o) {
+		sr_err("Invalid input module NULL!");
+		return NULL;
+	}
+
+	return o->desc;
+}
+
+/**
+ * Return the input module with the specified ID, or NULL if no module
+ * with that id is found.
+ *
+ * @since 0.4.0
+ */
+SR_API const struct sr_input_module *sr_input_find(char *id)
+{
+	int i;
+
+	for (i = 0; input_module_list[i]; i++) {
+		if (!strcmp(input_module_list[i]->id, id))
+			return input_module_list[i];
+	}
+
+	return NULL;
+}
+
+/**
+ * Returns a NULL-terminated array of struct sr_option, or NULL if the
+ * module takes no options.
+ *
+ * Each call to this function must be followed by a call to
+ * sr_input_options_free().
+ *
+ * @since 0.4.0
+ */
+SR_API const struct sr_option *sr_input_options_get(const struct sr_input_module *o)
+{
+
+	if (!o || !o->options)
+		return NULL;
+
+	return o->options();
+}
+
+/**
+ * After a call to sr_input_options_get(), this function cleans up all
+ * the resources allocated by that call.
+ *
+ * @since 0.4.0
+ */
+SR_API void sr_input_options_free(const struct sr_input_module *o)
+{
+	struct sr_option *opt;
+
+	if (!o || !o->options)
+		return;
+
+	for (opt = o->options(); opt->id; opt++) {
+		if (opt->def) {
+			g_variant_unref(opt->def);
+			opt->def = NULL;
+		}
+
+		if (opt->values) {
+			g_slist_free_full(opt->values, (GDestroyNotify)g_variant_unref);
+			opt->values = NULL;
+		}
+	}
+}
+
+/**
+ * Create a new input instance using the specified input module.
+ *
+ * This function is used when a client wants to use a specific input
+ * module to parse a stream. No effort is made to identify the format.
+ *
+ * <code>options</code> is a *HashTable with the keys corresponding with
+ * the module options' <code>id</code> field. The values should be GVariant
+ * pointers with sunk * references, of the same GVariantType as the option's
+ * default value.
+ *
+ * @since 0.4.0
+ */
+SR_API struct sr_input *sr_input_new(const struct sr_input_module *imod,
+		GHashTable *options)
+{
+	struct sr_input *in;
+	struct sr_option *mod_opts;
+	const GVariantType *gvt;
+	GHashTable *new_opts;
+	GHashTableIter iter;
+	gpointer key, value;
+	int i;
+
+	in = g_malloc0(sizeof(struct sr_input));
+	in->module = imod;
+
+	if (options) {
+		new_opts = g_hash_table_new_full(g_str_hash, g_str_equal, g_free,
+				(GDestroyNotify)g_variant_unref);
+		mod_opts = imod->options();
+		for (i = 0; mod_opts[i].id; i++) {
+			if (g_hash_table_lookup_extended(options, mod_opts[i].id,
+					&key, &value)) {
+				/* Option not given: insert the default value. */
+				gvt = g_variant_get_type(mod_opts[i].def);
+				if (!g_variant_is_of_type(value, gvt)) {
+					sr_err("Invalid type for '%s' option.", key);
+					g_free(in);
+					return NULL;
+				}
+				g_hash_table_insert(new_opts, g_strdup(mod_opts[i].id),
+						g_variant_ref(value));
+			} else {
+				/* Pass option along. */
+				g_hash_table_insert(new_opts, g_strdup(mod_opts[i].id),
+						g_variant_ref(mod_opts[i].def));
+			}
+		}
+
+		/* Make sure no invalid options were given. */
+		g_hash_table_iter_init(&iter, options);
+		while (g_hash_table_iter_next(&iter, &key, &value)) {
+			if (!g_hash_table_lookup(new_opts, key)) {
+				sr_err("Input module '%s' has no option '%s'", imod->id, key);
+				g_hash_table_destroy(new_opts);
+				g_free(in);
+				return NULL;
+			}
+		}
+	} else
+		new_opts = NULL;
+
+	if (in->module->init && in->module->init(in, new_opts) != SR_OK) {
+		g_hash_table_destroy(new_opts);
+		g_free(in);
+		in = NULL;
+	}
+	if (new_opts)
+		g_hash_table_destroy(new_opts);
+
+	return in;
+}
+
+/* Returns TRUE is all required meta items are available. */
+static gboolean check_required_metadata(const uint8_t *metadata, uint8_t *avail)
+{
+	int m, a;
+	uint8_t reqd;
+
+	for (m = 0; metadata[m]; m++) {
+		if (!metadata[m] & SR_INPUT_META_REQUIRED)
+			continue;
+		reqd = metadata[m] & ~SR_INPUT_META_REQUIRED;
+		for (a = 0; avail[a]; a++) {
+			if (avail[a] == reqd)
+				break;
+		}
+		if (!avail[a])
+			/* Found a required meta item that isn't available. */
+			return FALSE;
+	}
+
+	return TRUE;
+}
+
+/**
+ * Try to find an input module that can parse the given buffer.
+ *
+ * The buffer must contain enough of the beginning of the file for
+ * the input modules to find a match. This is format-dependent, but
+ * 128 bytes is normally enough.
+ *
+ * If an input module is found, an instance is created and returned.
+ * Otherwise, NULL is returned.
+ *
+ */
+SR_API const struct sr_input *sr_input_scan_buffer(GString *buf)
+{
+	struct sr_input *in;
+	const struct sr_input_module *imod;
+	GHashTable *meta;
+	unsigned int m, i;
+	uint8_t mitem, avail_metadata[8];
+
+	/* No more metadata to be had from a buffer. */
+	avail_metadata[0] = SR_INPUT_META_HEADER;
+	avail_metadata[1] = 0;
+
+	in = NULL;
+	for (i = 0; input_module_list[i]; i++) {
+		imod = input_module_list[i];
+		if (!imod->metadata[0]) {
+			/* Module has no metadata for matching so will take
+			 * any input. No point in letting it try to match. */
+			continue;
+		}
+		if (!check_required_metadata(imod->metadata, avail_metadata))
+			/* Cannot satisfy this module's requirements. */
+			continue;
+
+		meta = g_hash_table_new(NULL, NULL);
+		for (m = 0; m < sizeof(imod->metadata); m++) {
+			mitem = imod->metadata[m] & ~SR_INPUT_META_REQUIRED;
+			if (mitem == SR_INPUT_META_HEADER)
+				g_hash_table_insert(meta, GINT_TO_POINTER(mitem), buf);
+		}
+		if (g_hash_table_size(meta) == 0) {
+			/* No metadata for this module, so nothing to match. */
+			g_hash_table_destroy(meta);
+			continue;
+		}
+		if (!imod->format_match(meta)) {
+			/* Module didn't recognize this buffer. */
+			g_hash_table_destroy(meta);
+			continue;
+		}
+		g_hash_table_destroy(meta);
+
+		/* Found a matching module. */
+		in = sr_input_new(imod, NULL);
+		in->buf = g_string_new_len(buf->str, buf->len);
+		break;
+	}
+
+	return in;
+}
+
+/**
+ * Try to find an input module that can parse the given file.
+ *
+ * If an input module is found, an instance is created and returned.
+ * Otherwise, NULL is returned.
+ *
+ */
+SR_API const struct sr_input *sr_input_scan_file(const char *filename)
+{
+	struct sr_input *in;
+	const struct sr_input_module *imod;
+	GHashTable *meta;
+	GString *buf;
+	struct stat st;
+	unsigned int midx, m, i;
+	int fd;
+	ssize_t size;
+	uint8_t mitem, avail_metadata[8];
+
+	if (!filename || !filename[0]) {
+		sr_err("Invalid filename.");
+		return NULL;
+	}
+
+	if (!g_file_test(filename, G_FILE_TEST_EXISTS)) {
+		sr_err("No such file.");
+		return NULL;
+	}
+
+	if (stat(filename, &st) < 0) {
+		sr_err("%s", strerror(errno));
+		return NULL;
+	}
+
+	midx = 0;
+	avail_metadata[midx++] = SR_INPUT_META_FILENAME;
+	avail_metadata[midx++] = SR_INPUT_META_FILESIZE;
+	avail_metadata[midx++] = SR_INPUT_META_HEADER;
+	/* TODO: MIME type */
+
+	in = NULL;
+	buf = NULL;
+	for (i = 0; input_module_list[i]; i++) {
+		imod = input_module_list[i];
+		if (!imod->metadata[0]) {
+			/* Module has no metadata for matching so will take
+			 * any input. No point in letting it try to match. */
+			continue;
+		}
+		if (!check_required_metadata(imod->metadata, avail_metadata))
+			/* Cannot satisfy this module's requirements. */
+			continue;
+
+		meta = g_hash_table_new(NULL, NULL);
+		for (m = 0; m < sizeof(imod->metadata); m++) {
+			mitem = imod->metadata[m] & ~SR_INPUT_META_REQUIRED;
+			if (mitem == SR_INPUT_META_FILENAME)
+				g_hash_table_insert(meta, GINT_TO_POINTER(mitem),
+						(gpointer)filename);
+			else if (mitem == SR_INPUT_META_FILESIZE)
+				g_hash_table_insert(meta, GINT_TO_POINTER(mitem),
+						GINT_TO_POINTER(st.st_size));
+			else if (mitem == SR_INPUT_META_HEADER) {
+				buf = g_string_sized_new(128);
+				if ((fd = open(filename, O_RDONLY)) < 0) {
+					sr_err("%s", strerror(errno));
+					return NULL;
+				}
+				size = read(fd, buf->str, 128);
+				buf->len = size;
+				close(fd);
+				if (size <= 0) {
+					g_string_free(buf, TRUE);
+					sr_err("%s", strerror(errno));
+					return NULL;
+				}
+				g_hash_table_insert(meta, GINT_TO_POINTER(mitem), buf);
+				g_string_free(buf, TRUE);
+			}
+		}
+		if (g_hash_table_size(meta) == 0) {
+			/* No metadata for this module, so there's no way it
+			 * can match. */
+			g_hash_table_destroy(meta);
+			continue;
+		}
+		if (!imod->format_match(meta))
+			/* Module didn't recognize this buffer. */
+			continue;
+
+		/* Found a matching module. */
+		in = sr_input_new(imod, NULL);
+		in->buf = g_string_new_len(buf->str, buf->len);
+		break;
+	}
+	if (!in && buf)
+		g_string_free(buf, TRUE);
+
+	return in;
+}
+
+SR_API struct sr_dev_inst *sr_input_dev_inst_get(const struct sr_input *in)
+{
+	return in->sdi;
+}
+
+/**
+ * Send data to the specified input instance.
+ *
+ * When an input module instance is created with sr_input_new(), this
+ * function is used to feed data to the instance.
+ *
+ * @since 0.4.0
+ */
+SR_API int sr_input_send(const struct sr_input *in, GString *buf)
+{
+	return in->module->receive(in, buf);
+}
+
+/**
+ * Free the specified input instance and all associated resources.
+ *
+ * @since 0.4.0
+ */
+SR_API int sr_input_free(const struct sr_input *in)
+{
+	int ret;
+
+	if (!in)
+		return SR_ERR_ARG;
+
+	ret = SR_OK;
+	if (in->module->cleanup)
+		ret = in->module->cleanup((struct sr_input *)in);
+	if (in->buf)
+		g_string_free(in->buf, TRUE);
+	g_free((gpointer)in);
+
+	return ret;
+}
+
+
 /** @} */

src/input/vcd.c

@@ -537,7 +537,7 @@ static int loadfile(struct sr_input *in, const char *filename)
 
 SR_PRIV struct sr_input_module input_vcd = {
 	.id = "vcd",
-	.description = "Value Change Dump",
+	.desc = "Value Change Dump",
 	.format_match = format_match,
 	.init = init,
 	.loadfile = loadfile,

src/input/wav.c

@@ -30,6 +30,10 @@
 
 /* How many bytes at a time to process and send to the session bus. */
 #define CHUNK_SIZE 4096
+
+/* Minimum size of header + 1 8-bit mono PCM sample. */
+#define MIN_DATA_CHUNK_OFFSET    45
+
 /* Expect to find the "data" chunk within this offset from the start. */
 #define MAX_DATA_CHUNK_OFFSET    256
 
@@ -37,230 +41,278 @@
 #define WAVE_FORMAT_IEEE_FLOAT   3
 
 struct context {
+	int fmt_code;
 	uint64_t samplerate;
 	int samplesize;
 	int num_channels;
 	int unitsize;
-	int fmt_code;
+	gboolean found_data;
 };
 
-static int get_wav_header(const char *filename, char *buf)
+static int parse_wav_header(GString *buf, struct context *inc)
 {
-	struct stat st;
+	uint64_t samplerate;
-	int fd, l;
+	int fmt_code, samplesize, num_channels, unitsize;
 
-	l = strlen(filename);
+	if (buf->len < MIN_DATA_CHUNK_OFFSET) {
-	if (l <= 4 || strcasecmp(filename + l - 4, ".wav"))
 		return SR_ERR;
+	}
 
-	if (stat(filename, &st) == -1)
+	fmt_code = GUINT16_FROM_LE(*(uint16_t *)(buf->str + 20));
-		return SR_ERR;
+	samplerate = GUINT32_FROM_LE(*(uint32_t *)(buf->str + 24));
-	if (st.st_size <= 45)
+	samplesize = GUINT16_FROM_LE(*(uint16_t *)(buf->str + 32));
-		/* Minimum size of header + 1 8-bit mono PCM sample. */
+	num_channels = GUINT16_FROM_LE(*(uint16_t *)(buf->str + 22));
-		return SR_ERR;
+	/* TODO div0 */
+	unitsize = samplesize / num_channels;
 
-	if ((fd = open(filename, O_RDONLY)) == -1)
+	if (fmt_code == WAVE_FORMAT_PCM) {
+		if (samplesize != 1 && samplesize != 2 && samplesize != 4) {
+			sr_err("only 8, 16 or 32 bits per sample supported.");
+			return SR_ERR;
+		}
+	} else if (fmt_code == WAVE_FORMAT_IEEE_FLOAT) {
+		if (unitsize != 4) {
+			sr_err("only 32-bit floats supported.");
+			return SR_ERR;
+		}
+	} else {
+		sr_err("Only PCM and floating point samples are supported.");
 		return SR_ERR;
+	}
 
-	l = read(fd, buf, 40);
+	if (inc) {
-	close(fd);
+		inc->fmt_code = fmt_code;
-	if (l != 40)
+		inc->samplerate = samplerate;
-		return SR_ERR;
+		inc->samplesize = samplesize;
+		inc->num_channels = num_channels;
+		inc->unitsize = unitsize;
+		inc->found_data = FALSE;
+	}
 
 	return SR_OK;
 }
 
-static int format_match(const char *filename)
+static int format_match(GHashTable *metadata)
 {
-	char buf[40];
+	GString *buf;
-	uint16_t fmt_code;
 
-	if (get_wav_header(filename, buf) != SR_OK)
+	buf = g_hash_table_lookup(metadata, GINT_TO_POINTER(SR_INPUT_META_HEADER));
+	if (strncmp(buf->str, "RIFF", 4))
 		return FALSE;
-
+	if (strncmp(buf->str + 8, "WAVE", 4))
-	if (strncmp(buf, "RIFF", 4))
 		return FALSE;
-	if (strncmp(buf + 8, "WAVE", 4))
+	if (strncmp(buf->str + 12, "fmt ", 4))
 		return FALSE;
-	if (strncmp(buf + 12, "fmt ", 4))
+	/*
-		return FALSE;
+	 * Only gets called when we already know this is a WAV file, so
-	fmt_code = GUINT16_FROM_LE(*(uint16_t *)(buf + 20));
+	 * this parser can log error messages.
-	if (fmt_code != WAVE_FORMAT_PCM
+	 */
-			&& fmt_code != WAVE_FORMAT_IEEE_FLOAT)
+	if (parse_wav_header(buf, NULL) != SR_OK)
 		return FALSE;
 
 	return TRUE;
 }
 
-static int init(struct sr_input *in, const char *filename)
+static int init(struct sr_input *in, GHashTable *options)
 {
-	struct sr_channel *ch;
+	(void)options;
-	struct context *ctx;
-	char buf[40], channelname[8];
-	int i;
 
-	if (get_wav_header(filename, buf) != SR_OK)
-		return SR_ERR;
-
-	if (!(ctx = g_try_malloc0(sizeof(struct context))))
-		return SR_ERR_MALLOC;
-
-	/* Create a virtual device. */
 	in->sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, NULL, NULL, NULL);
-	in->sdi->priv = ctx;
-
-	ctx->fmt_code = GUINT16_FROM_LE(*(uint16_t *)(buf + 20));
-   	ctx->samplerate = GUINT32_FROM_LE(*(uint32_t *)(buf + 24));
-	ctx->samplesize = GUINT16_FROM_LE(*(uint16_t *)(buf + 32));
-	ctx->num_channels = GUINT16_FROM_LE(*(uint16_t *)(buf + 22));
-	ctx->unitsize = ctx->samplesize / ctx->num_channels;
-
-	if (ctx->fmt_code == WAVE_FORMAT_PCM) {
-		if (ctx->samplesize != 1 && ctx->samplesize != 2
-				&& ctx->samplesize != 4) {
-			sr_err("only 8, 16 or 32 bits per sample supported.");
-			return SR_ERR;
-		}
-	} else {
-		/* WAVE_FORMAT_IEEE_FLOAT */
-		if (ctx->samplesize / ctx->num_channels != 4) {
-			sr_err("only 32-bit floats supported.");
-			return SR_ERR;
-		}
-	}
-
-	for (i = 0; i < ctx->num_channels; i++) {
-		snprintf(channelname, 8, "CH%d", i + 1);
-		ch = sr_channel_new(i, SR_CHANNEL_ANALOG, TRUE, channelname);
-		in->sdi->channels = g_slist_append(in->sdi->channels, ch);
-	}
 
 	return SR_OK;
 }
 
-static int find_data_chunk(uint8_t *buf, int initial_offset)
+static int find_data_chunk(GString *buf, int initial_offset)
 {
-	int offset, i;
+	unsigned int offset, i;
 
 	offset = initial_offset;
-	while(offset < MAX_DATA_CHUNK_OFFSET) {
+	while(offset < MIN(MAX_DATA_CHUNK_OFFSET, buf->len)) {
-		if (!memcmp(buf + offset, "data", 4))
+		if (!memcmp(buf->str + offset, "data", 4))
 			/* Skip into the samples. */
 			return offset + 8;
 		for (i = 0; i < 4; i++) {
-			if (!isalpha(buf[offset + i])
+			if (!isalpha(buf->str[offset + i])
-					&& !isascii(buf[offset + i])
+					&& !isascii(buf->str[offset + i])
-					&& !isblank(buf[offset + i]))
+					&& !isblank(buf->str[offset + i]))
 				/* Doesn't look like a chunk ID. */
 				return -1;
 		}
 		/* Skip past this chunk. */
-		offset += 8 + GUINT32_FROM_LE(*(uint32_t *)(buf + offset + 4));
+		offset += 8 + GUINT32_FROM_LE(*(uint32_t *)(buf->str + offset + 4));
 	}
 
 	return offset;
 }
 
-static int loadfile(struct sr_input *in, const char *filename)
+static int initial_receive(const struct sr_input *in)
 {
 	struct sr_datafeed_packet packet;
 	struct sr_datafeed_meta meta;
-	struct sr_datafeed_analog analog;
+	struct sr_channel *ch;
 	struct sr_config *src;
-	struct context *ctx;
+	struct context *inc;
-	float fdata[CHUNK_SIZE];
+	int i;
-	uint64_t sample;
+	char channelname[8];
-	int offset, chunk_samples, samplenum, fd, l, i;
-	uint8_t buf[CHUNK_SIZE], *s, *d;
 
-	ctx = in->sdi->priv;
+	if (!in->buf)
+		/* Shouldn't happen. */
+		return SR_ERR;
+
+	inc = in->sdi->priv = g_malloc(sizeof(struct context));
+	if (parse_wav_header(in->buf, inc) != SR_OK)
+		return SR_ERR;
+
+	for (i = 0; i < inc->num_channels; i++) {
+		snprintf(channelname, 8, "CH%d", i + 1);
+		ch = sr_channel_new(i, SR_CHANNEL_ANALOG, TRUE, channelname);
+		in->sdi->channels = g_slist_append(in->sdi->channels, ch);
+	}
 
-	/* Send header packet to the session bus. */
 	std_session_send_df_header(in->sdi, LOG_PREFIX);
 
-	/* Send the samplerate. */
 	packet.type = SR_DF_META;
 	packet.payload = &meta;
-	src = sr_config_new(SR_CONF_SAMPLERATE,
+	src = sr_config_new(SR_CONF_SAMPLERATE, g_variant_new_uint64(inc->samplerate));
-			g_variant_new_uint64(ctx->samplerate));
 	meta.config = g_slist_append(NULL, src);
 	sr_session_send(in->sdi, &packet);
 	sr_config_free(src);
 
-	if ((fd = open(filename, O_RDONLY)) == -1)
+	return SR_OK;
-		return SR_ERR;
+}
-	if (read(fd, buf, MAX_DATA_CHUNK_OFFSET) < MAX_DATA_CHUNK_OFFSET)
-		return -1;
 
-	/* Skip past size of 'fmt ' chunk. */
+static void send_chunk(const struct sr_input *in, int offset, int num_samples)
-	i = 20 + GUINT32_FROM_LE(*(uint32_t *)(buf + 16));
+{
-	offset = find_data_chunk(buf, i);
+	struct sr_datafeed_packet packet;
-	if (offset < 0) {
+	struct sr_datafeed_analog analog;
-		sr_err("Couldn't find data chunk.");
+	struct context *inc;
-		return SR_ERR;
+	float fdata[CHUNK_SIZE];
-	}
+	uint64_t sample;
-	if (lseek(fd, offset, SEEK_SET) == -1)
+	int total_samples, samplenum;
-		return SR_ERR;
+	char *s, *d;
 
+	inc = in->sdi->priv;
+
+	s = in->buf->str + offset;
+	d = (char *)fdata;
 	memset(fdata, 0, CHUNK_SIZE);
-	while (TRUE) {
+	total_samples = num_samples * inc->num_channels;
-		if ((l = read(fd, buf, CHUNK_SIZE)) < 1)
+	for (samplenum = 0; samplenum < total_samples; samplenum++) {
-			break;
+		if (inc->fmt_code == WAVE_FORMAT_PCM) {
-		chunk_samples = l / ctx->num_channels / ctx->unitsize;
+			sample = 0;
-		s = buf;
+			memcpy(&sample, s, inc->unitsize);
-		d = (uint8_t *)fdata;
+			switch (inc->samplesize) {
-		for (samplenum = 0; samplenum < chunk_samples * ctx->num_channels; samplenum++) {
+			case 1:
-			if (ctx->fmt_code == WAVE_FORMAT_PCM) {
+				/* 8-bit PCM samples are unsigned. */
-				sample = 0;
+				fdata[samplenum] = (uint8_t)sample / 255.0;
-				memcpy(&sample, s, ctx->unitsize);
+				break;
-				switch (ctx->samplesize) {
+			case 2:
-				case 1:
+				fdata[samplenum] = GINT16_FROM_LE(sample) / 32767.0;
-					/* 8-bit PCM samples are unsigned. */
+				break;
-					fdata[samplenum] = (uint8_t)sample / 255.0;
+			case 4:
-					break;
+				fdata[samplenum] = GINT32_FROM_LE(sample) / 65535.0;
-				case 2:
+				break;
-					fdata[samplenum] = GINT16_FROM_LE(sample) / 32767.0;
-					break;
-				case 4:
-					fdata[samplenum] = GINT32_FROM_LE(sample) / 65535.0;
-					break;
-				}
-			} else {
-				/* BINARY32 float */
-#ifdef WORDS_BIGENDIAN
-				for (i = 0; i < ctx->unitsize; i++)
-					d[i] = s[ctx->unitsize - i];
-#else
-				memcpy(d, s, ctx->unitsize);
-#endif
 			}
-			s += ctx->unitsize;
+		} else {
-			d += ctx->unitsize;
+			/* BINARY32 float */
-
+#ifdef WORDS_BIGENDIAN
+			for (i = 0; i < inc->unitsize; i++)
+				d[i] = s[inc->unitsize - i];
+#else
+			memcpy(d, s, inc->unitsize);
+#endif
 		}
-		packet.type = SR_DF_ANALOG;
+		s += inc->unitsize;
-		packet.payload = &analog;
+		d += inc->unitsize;
-		analog.channels = in->sdi->channels;
+	}
-		analog.num_samples = chunk_samples;
+	packet.type = SR_DF_ANALOG;
-		analog.mq = 0;
+	packet.payload = &analog;
-		analog.unit = 0;
+	analog.channels = in->sdi->channels;
-		analog.data = fdata;
+	analog.num_samples = num_samples;
+	analog.mq = 0;
+	analog.mqflags = 0;
+	analog.unit = 0;
+	analog.data = fdata;
+	sr_session_send(in->sdi, &packet);
+}
+
+static int receive(const struct sr_input *in, GString *buf)
+{
+	struct sr_datafeed_packet packet;
+	struct context *inc;
+	int offset, chunk_samples, total_samples, processed, max_chunk_samples, num_samples, i;
+
+	if (buf->len == 0) {
+		/* End of stream. */
+		packet.type = SR_DF_END;
 		sr_session_send(in->sdi, &packet);
+		return SR_OK;
 	}
 
-	close(fd);
+	g_string_append_len(in->buf, buf->str, buf->len);
-	packet.type = SR_DF_END;
+
-	sr_session_send(in->sdi, &packet);
+	if (!in->sdi->priv) {
+		if (initial_receive(in) != SR_OK)
+			return SR_ERR;
+		if (in->buf->len < MIN_DATA_CHUNK_OFFSET) {
+			/*
+			 * Don't even get started until there's enough room
+			 * for the data segment to start.
+			 */
+			return SR_OK;
+		}
+	}
+	inc = in->sdi->priv;
+
+	if (!inc->found_data) {
+		/* Skip past size of 'fmt ' chunk. */
+		i = 20 + GUINT32_FROM_LE(*(uint32_t *)(in->buf->str + 16));
+		offset = find_data_chunk(in->buf, i);
+		if (offset < 0) {
+			if (in->buf->len > MAX_DATA_CHUNK_OFFSET) {
+				sr_err("Couldn't find data chunk.");
+				return SR_ERR;
+			}
+		}
+		inc->found_data = TRUE;
+	} else
+		offset = 0;
+
+	/* Round off up to the last channels * unitsize boundary. */
+	chunk_samples = (in->buf->len - offset) / inc->num_channels / inc->unitsize;
+	max_chunk_samples = CHUNK_SIZE / inc->num_channels / inc->unitsize;
+	processed = 0;
+	total_samples = chunk_samples;
+	while (processed < total_samples) {
+		if (chunk_samples > max_chunk_samples)
+			num_samples = max_chunk_samples;
+		else
+			num_samples = chunk_samples;
+		send_chunk(in, offset, num_samples);
+		offset += num_samples * inc->unitsize;
+		chunk_samples -= num_samples;
+		processed += num_samples;
+	}
+
+	if ((unsigned int)offset < in->buf->len) {
+		/*
+		 * The incoming buffer wasn't processed completely. Stash
+		 * the leftover data for next time.
+		 */
+		g_string_erase(in->buf, 0, offset);
+	} else
+		g_string_truncate(in->buf, 0);
 
 	return SR_OK;
 }
 
-
 SR_PRIV struct sr_input_module input_wav = {
 	.id = "wav",
-	.description = "WAV file",
+	.name = "WAV",
+	.desc = "WAV file",
+	.metadata = { SR_INPUT_META_HEADER | SR_INPUT_META_REQUIRED },
 	.format_match = format_match,
 	.init = init,
-	.loadfile = loadfile,
+	.receive = receive,
 };
 

src/libsigrok-internal.h

@@ -172,37 +172,66 @@ struct sr_context {
 struct sr_input {
 	/**
 	 * A pointer to this input module's 'struct sr_input_module'.
-	 * The frontend can use this to call the module's callbacks.
 	 */
-	struct sr_input_module *module;
+	const struct sr_input_module *module;
-
+	GString *buf;
-	GHashTable *param;
-
 	struct sr_dev_inst *sdi;
-
+	void *priv;
-	void *internal;
 };
 
 /** Input (file) module driver. */
 struct sr_input_module {
-	/** The unique ID for this input module. Must not be NULL. */
-	char *id;
-
 	/**
-	 * A short description of the input module, which can (for example)
+	 * A unique ID for this output module, suitable for use in command-line
-	 * be displayed to the user by frontends. Must not be NULL.
+	 * clients, [a-z0-9-]. Must not be NULL.
 	 */
-	char *description;
+	const char *id;
 
 	/**
-	 * Check if this input module can load and parse the specified file.
+	 * A unique name for this output module, suitable for use in GUI
+	 * clients, can contain UTF-8. Must not be NULL.
+	 */
+	const char *name;
+
+	/**
+	 * A short description of the output module. Must not be NULL.
 	 *
-	 * @param[in] filename The name (and path) of the file to check.
+	 * This can be displayed by frontends, e.g. when selecting the output
+	 * module for saving a file.
+	 */
+	const char *desc;
+
+	/**
+	 * Zero-terminated list of metadata items the module needs to be able
+	 * to identify an input stream. Can be all-zero, if the module cannot
+	 * identify streams at all, i.e. has to be forced into use.
+	 *
+	 * Each item is one of:
+	 *   SR_INPUT_META_FILENAME
+	 *   SR_INPUT_META_FILESIZE
+	 *   SR_INPUT_META_HEADER
+	 *   SR_INPUT_META_MIMETYPE
+	 *
+	 * If the high bit (SR_INPUT META_REQUIRED) is set, the module cannot
+	 * identify a stream without the given metadata.
+	 */
+	const uint8_t metadata[8];
+
+	/**
+	 * Returns a NULL-terminated list of options this module can take.
+	 * Can be NULL, if the module has no options.
+	 */
+	struct sr_option *(*options) (void);
+
+	/**
+	 * Check if this input module can load and parse the specified stream.
+	 *
+	 * @param[in] metadata Metadata the module can use to identify the stream.
 	 *
 	 * @retval TRUE This module knows the format.
 	 * @retval FALSE This module does not know the format.
 	 */
-	int (*format_match) (const char *filename);
+	int (*format_match) (GHashTable *metadata);
 
 	/**
 	 * Initialize the input module.
@@ -215,7 +244,7 @@ struct sr_input_module {
 	 * @retval SR_OK Success
 	 * @retval other Negative error code.
 	 */
-	int (*init) (struct sr_input *in, const char *filename);
+	int (*init) (struct sr_input *in, GHashTable *options);
 
 	/**
 	 * Load a file, parsing the input according to the file's format.
@@ -232,12 +261,22 @@ struct sr_input_module {
 	 * @param in A pointer to a valid 'struct sr_input' that the caller
 	 *           has to allocate and provide to this function. It is also
 	 *           the responsibility of the caller to free it later.
-	 * @param filename The name (and path) of the file to use.
+	 * @param f The name (and path) of the file to use.
 	 *
 	 * @retval SR_OK Success
 	 * @retval other Negative error code.
 	 */
-	int (*loadfile) (struct sr_input *in, const char *filename);
+	int (*receive) (const struct sr_input *in, GString *buf);
+
+	/**
+	 * This function is called after the caller is finished using
+	 * the input module, and can be used to free any internal
+	 * resources the module may keep.
+	 *
+	 * @retval SR_OK Success
+	 * @retval other Negative error code.
+	 */
+	int (*cleanup) (struct sr_input *in);
 };
 
 /** Output module instance. */

src/output/output.c

@@ -1,7 +1,7 @@
 /*
  * This file is part of the libsigrok project.
  *
- * Copyright (C) 2010-2012 Bert Vermeulen <bert@biot.com>
+ * Copyright (C) 2014 Bert Vermeulen <bert@biot.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