now with a special generation mode!

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

3 files changed, 161 insertions, 86 deletions

diff --git a/src/io.c b/src/io.c
index a8dfa2f..f10269c 100644
--- a/src/io.c
+++ b/src/io.c
@@ -10,11 +10,12 @@
 #include <libgen.h>
 #include "io.h"
 
-int stream_open(struct stream *in)
+static int stream_open_in(struct stream * const in);
+static int stream_open_out(struct stream * const in);
+static int stream_open_special(struct stream * const in);
+
+int stream_open(struct stream * const in)
 {
-	struct stat st;
-	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP;
-	char *dname = NULL;
 	int ret = 0;
 
 	if (!in || in->fd > 0 || !in->name) {
@@ -22,74 +23,19 @@ int stream_open(struct stream *in)
 		goto err;
 	}
 
-	if (in->out) {
-		char *tmp[2];
-
-		tmp[0] = strdup(in->name);
-		tmp[1] = dirname(tmp[0]);
-		dname = strdup(tmp[1]);
-		free(tmp[0]);
-
-		if (stat(dname, &st)) {
-			ret = errno;
-			/* TODO: error message */
-			goto err;
-		}
-
-		if(!(st.st_mode & S_IFDIR)) {
-			ret = EINVAL;
-			/* TODO: error message */
-			goto err;
-		}
-
-		if (!stat(in->name, &st)) {
-			if (!(st.st_mode & S_IFREG)) {
-				ret = EINVAL;
-				/* TODO: error message */
-				goto err;
-			}
-			mode = st.st_mode;
-		}
-	} else if (stat(in->name, &st)) {
-		ret = errno;
-		/* TODO: error message */
-		goto err;
-	} else if (!(st.st_mode & S_IFREG) || !st.st_size || (st.st_size % in->stride)) {
-		ret = EINVAL;
-		/* TODO: error message */
-		goto err;
+	if (in->out == 1) {
+		ret = stream_open_out(in);
+	} else if (!in->out) {
+		ret = stream_open_in(in);
 	} else {
-		in->n = st.st_size / in->stride;
-	}
-
-	if (in->out) {
-		in->fd = open(dname, O_TMPFILE | O_WRONLY, mode);
-		if (in->fd < 0) {
-			ret = errno;
-			/* TODO: error message */
-			goto err;
-		}
-
-		if (ftruncate(in->fd, in->stride * in->n)) {
-			ret = errno;
-			/* TODO: error message */
-			goto err;
-		}
-	} else {
-		in->fd = open(in->name, O_RDONLY | O_NOATIME);
-		if (in->fd < 0) {
-			ret = errno;
-			/* TODO: error message */
-			goto err;
-		}
+		ret = stream_open_special(in);
 	}
 
 err:
-	free(dname);
 	return ret;
 }
 
-int stream_close(struct stream *in)
+int stream_close(struct stream * const in)
 {
 	int ret = 0;
 
@@ -135,3 +81,108 @@ err:
 early_err:
 	return ret;
 }
+
+static int stream_open_out(struct stream * const in)
+{
+	struct stat st;
+	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP;
+	char *dname = NULL;
+	char *tmp[2];
+	int ret = 0;
+
+	tmp[0] = strdup(in->name);
+	tmp[1] = dirname(tmp[0]);
+	dname = strdup(tmp[1]);
+	free(tmp[0]);
+
+	if (stat(dname, &st)) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	}
+
+	if(!(st.st_mode & S_IFDIR)) {
+		ret = EINVAL;
+		/* TODO: error message */
+		goto err;
+	}
+
+	if (!stat(in->name, &st)) {
+		if (!(st.st_mode & S_IFREG)) {
+			ret = EINVAL;
+			/* TODO: error message */
+			goto err;
+		}
+		mode = st.st_mode;
+	}
+
+	in->fd = open(dname, O_TMPFILE | O_WRONLY, mode);
+
+	if (in->fd < 0) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	}
+
+	if (ftruncate(in->fd, in->stride * in->n)) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	}
+
+err:
+	free(dname);
+	return ret;
+}
+
+static int stream_open_in(struct stream * const in)
+{
+	struct stat st;
+	int ret = 0;
+
+	if (stat(in->name, &st)) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	} else if (!(st.st_mode & S_IFREG) || !st.st_size || (st.st_size % in->stride)) {
+		ret = EINVAL;
+		/* TODO: error message */
+		goto err;
+	} else {
+		in->n = st.st_size / in->stride;
+	}
+
+	in->fd = open(in->name, O_RDONLY | O_NOATIME);
+
+	if (in->fd < 0) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	}
+
+err:
+	return ret;
+}
+
+static int stream_open_special(struct stream * const in)
+{
+	struct stat st;
+	int ret = 0;
+
+	if (stat(in->name, &st)) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	}
+
+	in->fd = open(in->name, O_RDONLY | O_NOATIME);
+
+	if (in->fd < 0) {
+		ret = errno;
+		/* TODO: error message */
+		goto err;
+	}
+
+err:
+	return ret;
+}
diff --git a/src/io.h b/src/io.h
index b7c0ebd..18e8e65 100644
--- a/src/io.h
+++ b/src/io.h
@@ -24,7 +24,9 @@ struct entry_l {
 	uint64_t val;
 };
 
-int stream_open(struct stream *in);
-int stream_close(struct stream *in);
+int stream_open(struct stream * const in);
+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);
 
 #endif /* ALGOS_IO_H_INCLUDED */
diff --git a/src/main.c b/src/main.c
index 29283a6..ee0ad52 100644
--- a/src/main.c
+++ b/src/main.c
@@ -5,16 +5,24 @@
 #include <string.h>
 #include "io.h"
 
-static const unsigned int OPERATING_MODE = (1 << 0);
-static const unsigned int DATA_FORMAT =    (1 << 1);
-static const unsigned int DATA_ACCESS =    (1 << 2);
+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 fetchpos;
-	size_t fetchto;
+	size_t ss;
+	size_t to;
 	char *filein;
 	char *fileout;
-	unsigned int mode;
+	unsigned int flags;
+	enum opmode opmode;
 } settings = {0};
 
 static struct stream file_in = {.last_idx = -1, .fd = -1};
@@ -31,14 +39,20 @@ int main(int argc, char **argv)
 		goto out;
 	}
 
-	file_in.name = settings.filein;
-	file_in.stride = settings.mode & DATA_FORMAT ? sizeof(struct entry_l) : sizeof(struct entry_a);
+	if (settings.opmode == mode_generate) {
+		file_in.name = randfile;
+		file_in.out = -1;
+	} 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))) {
 		goto out;
 	}
 
-	file_out.name = settings.fileout ? settings.fileout : settings.filein;
 	file_out.n = file_in.n;
 	file_out.stride = file_in.stride;
 
@@ -64,26 +78,28 @@ static int parseargs(int argc, char **argv, struct settings_s * settings)
 
 	for (i = 1; i < argc - 1; ++i) {
 		if (!(strcmp(argv[i], "--sort"))) {
-			s.mode &= ~OPERATING_MODE;
+			s.opmode = mode_normal;
 		} else if (!(strcmp(argv[i], "--fetch"))) {
-			s.mode |= OPERATING_MODE;
+			s.opmode = mode_fetch;
+		} else if (!(strcmp(argv[i], "--generate"))) {
+			s.opmode = mode_generate;
 		} else if (!(strcmp(argv[i], "--array"))) {
-			s.mode &= ~DATA_FORMAT;
+			s.opmode &= ~FLAG_DATA_FORMAT;
 		} else if (!(strcmp(argv[i], "--list"))) {
-			s.mode |= DATA_FORMAT;
+			s.opmode |= FLAG_DATA_FORMAT;
 		} else if (!(strcmp(argv[i], "--cache"))) {
-			s.mode &= ~DATA_ACCESS;
+			s.opmode &= ~FLAG_DATA_ACCESS;
 		} else if (!(strcmp(argv[i], "--no-cache"))) {
-			s.mode |= DATA_ACCESS;
+			s.opmode |= FLAG_DATA_ACCESS;
 		} else if (!(strncmp(argv[i], "--position=", 11))) {
 			if (strlen(argv[i]) > 11) {
-				s.fetchpos = strtoul(argv[i] + 11, NULL, 10);
+				s.ss = strtoul(argv[i] + 11, NULL, 10);
 			} else {
 				goto err;
 			}
 		} else if (!(strncmp(argv[i], "--num=", 6))) {
 			if (strlen(argv[i]) > 6) {
-				s.fetchto = strtoul(argv[i] + 11, NULL, 10);
+				s.to = strtoul(argv[i] + 11, NULL, 10);
 			} else {
 				goto err;
 			}
@@ -108,7 +124,12 @@ static int parseargs(int argc, char **argv, struct settings_s * settings)
 		s.fileout = s.filein;
 	}
 
-	s.fetchto = s.fetchpos + s.fetchto;
+	s.to = s.ss + s.to;
+
+	/* we always generate in-memory for speed */
+	if (s.opmode == mode_generate) {
+		s.opmode &= ~FLAG_DATA_ACCESS;
+	}
 
 	*settings = s;
 
@@ -130,11 +151,12 @@ void printhelp(const char * const name)
 		"Options:\n"
 		" --sort              sort mode (default)\n"
 		" --fetch             do not sort, fetch element(s) instead\n"
+		" --generate          generate an input dataset\n"
 		" --array             use an array data format (default)\n"
 		" --list              use a linked list data format\n"
 		" --[no]-cache        cache data in memory (default) or process data in-place\n"
 		" --position=<num>    fetch element from position <num>\n"
-		" --num=<num>         <num> of elements to fetch\n"
+		" --num=<num>         <num> of elements to fetch/generate\n"
 		" --out=<name>        write output to <name> file\n"
 		"\n"
 		"In case more than one same option is provided, the last one take precedence\n"