now with a special generation mode!

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

1 files changed, 41 insertions, 19 deletions

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"