implement reading from dev-you-random for datagen.

Signed-off-by: Gediminas Jakutis <gediminas@varciai.lt>

7 files changed, 113 insertions, 63 deletions

diff --git a/src/datagen.c b/src/datagen.c
new file mode 100644
index 0000000..9efe3b3
--- /dev/null
+++ b/src/datagen.c
@@ -0,0 +1,25 @@
+#include <unistd.h>
+#include <stddef.h>
+#include <errno.h>
+#include "datagen.h"
+#include "defs.h"
+
+int gen_get(struct stream *in, size_t idx, struct entry_l *data, int tag)
+{
+	int ret = 0;
+	(void) idx;
+
+	if (tag) {
+		data->prev = 0;
+		data->next = 0;
+	}
+
+	in->prev_idx = -1;
+	ret = read(in->fd, &data->val, sizeof(data->val));
+
+	if (ret != sizeof(data->val)) {
+		ret = ret > 0 ? EAGAIN : errno;
+	}
+
+	return ret;
+}
diff --git a/src/datagen.h b/src/datagen.h
new file mode 100644
index 0000000..7e753ab
--- /dev/null
+++ b/src/datagen.h
@@ -0,0 +1,8 @@
+#ifndef ALGOS_DATAGEN_H_INCLUDED
+#define ALGOS_DATAGEN_H_INCLUDED
+
+#include "defs.h"
+
+int gen_get(struct stream *in, size_t idx, struct entry_l *data, int tag);
+
+#endif /* ALGOS_DATAGEN_H_INCLUDED */
diff --git a/src/defs.h b/src/defs.h
new file mode 100644
index 0000000..b06e181
--- /dev/null
+++ b/src/defs.h
@@ -0,0 +1,46 @@
+#ifndef ALGOS_DEFS_H_INCLUDED
+#define ALGOS_DEFS_H_INCLUDED
+
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+
+/* for array implementation */
+struct entry {
+	uint64_t val;
+};
+
+/* for linked list implementation */
+struct entry_l {
+	struct entry;
+	uint32_t next; /* """pointer""" to the next element. */
+	uint32_t prev; /* """pointer""" to the previous element. */
+};
+
+enum opmode {
+	mode_normal,
+	mode_fetch,
+	mode_generate
+};
+
+struct stream {
+	size_t n;
+	ssize_t prev_idx;
+	int fd;
+	int out;
+	char *name;
+};
+
+struct settings {
+	size_t ss;
+	size_t to;
+	size_t stride;
+	char *filein;
+	char *fileout;
+	unsigned int flags;
+	enum opmode opmode;
+	int (*get)(struct stream, size_t, struct entry_l *, int);
+	int (*put)(struct stream, size_t, struct entry_l *, int);
+};
+
+#endif /* ALGOS_DEFS_H_INCLUDED */
diff --git a/src/io.c b/src/io.c
index f10269c..edcda17 100644
--- a/src/io.c
+++ b/src/io.c
@@ -9,24 +9,25 @@
 #include <string.h>
 #include <libgen.h>
 #include "io.h"
+#include "defs.h"
 
-static int stream_open_in(struct stream * const in);
-static int stream_open_out(struct stream * const in);
+static int stream_open_in(struct stream * const in, const struct settings * const s);
+static int stream_open_out(struct stream * const in, const struct settings * const s);
 static int stream_open_special(struct stream * const in);
 
-int stream_open(struct stream * const in)
+int stream_open(struct stream * const in, const struct settings * const s)
 {
 	int ret = 0;
 
-	if (!in || in->fd > 0 || !in->name) {
+	if (!in || in->fd > 0 || !in->name || !s) {
 		ret = EINVAL;
 		goto err;
 	}
 
 	if (in->out == 1) {
-		ret = stream_open_out(in);
+		ret = stream_open_out(in, s);
 	} else if (!in->out) {
-		ret = stream_open_in(in);
+		ret = stream_open_in(in, s);
 	} else {
 		ret = stream_open_special(in);
 	}
@@ -82,7 +83,7 @@ early_err:
 	return ret;
 }
 
-static int stream_open_out(struct stream * const in)
+static int stream_open_out(struct stream * const in, const struct settings * const s)
 {
 	struct stat st;
 	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP;
@@ -124,7 +125,7 @@ static int stream_open_out(struct stream * const in)
 		goto err;
 	}
 
-	if (ftruncate(in->fd, in->stride * in->n)) {
+	if (ftruncate(in->fd, s->stride * in->n)) {
 		ret = errno;
 		/* TODO: error message */
 		goto err;
@@ -135,7 +136,7 @@ err:
 	return ret;
 }
 
-static int stream_open_in(struct stream * const in)
+static int stream_open_in(struct stream * const in, const struct settings * const s)
 {
 	struct stat st;
 	int ret = 0;
@@ -144,12 +145,12 @@ static int stream_open_in(struct stream * const in)
 		ret = errno;
 		/* TODO: error message */
 		goto err;
-	} else if (!(st.st_mode & S_IFREG) || !st.st_size || (st.st_size % in->stride)) {
+	} else if (!(st.st_mode & S_IFREG) || !st.st_size || (st.st_size % s->stride)) {
 		ret = EINVAL;
 		/* TODO: error message */
 		goto err;
 	} else {
-		in->n = st.st_size / in->stride;
+		in->n = st.st_size / s->stride;
 	}
 
 	in->fd = open(in->name, O_RDONLY | O_NOATIME);
diff --git a/src/io.h b/src/io.h
index 18e8e65..d76f2b3 100644
--- a/src/io.h
+++ b/src/io.h
@@ -1,32 +1,11 @@
 #ifndef ALGOS_IO_H_INCLUDED
 #define ALGOS_IO_H_INCLUDED
 
-#include <stddef.h>
-#include <stdint.h>
+#include "defs.h"
 
-struct stream {
-	size_t n;
-	size_t stride;
-	ssize_t last_idx;
-	int fd;
-	int out;
-	char *name;
-};
-
-/* for array implementation */
-struct entry_a {
-	uint64_t val;
-};
-
-/* for linked list implementation */
-struct entry_l {
-	uint32_t i; /* "pointer" to the next element. */
-	uint64_t val;
-};
-
-int stream_open(struct stream * const in);
+int stream_open(struct stream * const in, const struct settings * const s);
 int stream_close(struct stream * const in);
-int stream_get(struct stream *in, size_t idx, void *data);
-int stream_put(struct stream *in, size_t idx, void *data);
+int stream_get(struct stream *in, size_t idx, struct entry_l *data, int tag);
+int stream_put(struct stream *in, size_t idx, struct entry_l *data, int tag);
 
 #endif /* ALGOS_IO_H_INCLUDED */
diff --git a/src/main.c b/src/main.c
index ee0ad52..ca3b600 100644
--- a/src/main.c
+++ b/src/main.c
@@ -5,30 +5,17 @@
 #include <string.h>
 #include "io.h"
 
-enum opmode {
-	mode_normal,
-	mode_fetch,
-	mode_generate
-};
-
 static const unsigned int FLAG_DATA_FORMAT = (1 << 0);
 static const unsigned int FLAG_DATA_ACCESS = (1 << 1);
 
 static char randfile[] = "/dev/urandom";
 
-static struct settings_s {
-	size_t ss;
-	size_t to;
-	char *filein;
-	char *fileout;
-	unsigned int flags;
-	enum opmode opmode;
-} settings = {0};
+static struct settings settings = {0};
 
-static struct stream file_in = {.last_idx = -1, .fd = -1};
-static struct stream file_out = {.last_idx = -1, .fd = -1, .out = 1};
+static struct stream file_in = {.prev_idx = -1, .fd = -1};
+static struct stream file_out = {.prev_idx = -1, .fd = -1, .out = 1};
 
-static int parseargs(int argc, char **argv, struct settings_s * settings);
+static int parseargs(int argc, char **argv, struct settings * settings);
 void printhelp(const char * const name);
 
 int main(int argc, char **argv)
@@ -42,21 +29,19 @@ int main(int argc, char **argv)
 	if (settings.opmode == mode_generate) {
 		file_in.name = randfile;
 		file_in.out = -1;
+		file_in.n = settings.to;
+		file_out.n = settings.to;
 	} else {
 		file_in.name = settings.filein;
 	}
 
 	file_out.name = settings.fileout ? settings.fileout : settings.filein;
-	file_in.stride = settings.opmode & FLAG_DATA_FORMAT ? sizeof(struct entry_l) : sizeof(struct entry_a);
 
-	if ((ret = stream_open(&file_in))) {
+	if ((ret = stream_open(&file_in, &settings))) {
 		goto out;
 	}
 
-	file_out.n = file_in.n;
-	file_out.stride = file_in.stride;
-
-	if ((ret = stream_open(&file_out))) {
+	if ((ret = stream_open(&file_out, &settings))) {
 		goto out;
 	}
 
@@ -66,9 +51,9 @@ out:
 	return ret;
 }
 
-static int parseargs(int argc, char **argv, struct settings_s * settings)
+static int parseargs(int argc, char **argv, struct settings * settings)
 {
-	struct settings_s s = {0};
+	struct settings s = {0};
 	ssize_t i;
 	int ret = 0;
 
@@ -124,13 +109,16 @@ static int parseargs(int argc, char **argv, struct settings_s * settings)
 		s.fileout = s.filein;
 	}
 
-	s.to = s.ss + s.to;
 
-	/* we always generate in-memory for speed */
 	if (s.opmode == mode_generate) {
+		/* we always generate in-memory for speed */
 		s.opmode &= ~FLAG_DATA_ACCESS;
+	} else if (s.opmode == mode_fetch) {
+		s.to = s.ss + s.to;
 	}
 
+	s.stride = s.opmode & FLAG_DATA_FORMAT ? sizeof(struct entry_l) : sizeof(struct entry);
+
 	*settings = s;
 
 	while (0) {
diff --git a/src/meson.build b/src/meson.build
index 13ff4d7..f353e54 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -1,10 +1,13 @@
 source_files = [
 	'main.c',
 	'io.c',
+	'datagen.c',
 ]
 
 header_files = [
 	'io.h',
+	'defs.h',
+	'datagen.h',
 ]
 
 sources = files(source_files)