1 files changed, 98 insertions, 0 deletions
diff --git a/hash.c b/hash.c
new file mode 100644
index 0000000..0784c78
--- /dev/null
+++ b/hash.c
@@ -0,0 +1,98 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+size_t
+inithashers(struct algorithm *algorithms, size_t nalgorithms)
+{
+	size_t i;
+	for (i = 0; i < nalgorithms;) {
+		if (libhashsum_init_hasher_from_string(&algorithms[i].hasher, algorithms[i].algostr)) {
+			weprintf("%s:", algorithms[i].algostr);
+			free(algorithms[i].result);
+			/* keep order */
+			memmove(&algorithms[i], &algorithms[i + 1U], (--nalgorithms - i) * sizeof(*algorithms));
+		} else {
+			algorithms[i].offset = 0;
+			i++;
+		}
+	}
+	return nalgorithms;
+}
+
+
+void
+destroyhashers(struct algorithm *algorithms, size_t nalgorithms)
+{
+	size_t i;
+	for (i = 0; i < nalgorithms; i++)
+		if (algorithms[i].hasher.destroy)
+			algorithms[i].hasher.destroy(&algorithms[i].hasher);
+}
+
+
+static void
+process(struct algorithm *algorithm, struct global_data *global)
+{
+	size_t r;
+	r = algorithm->hasher.process(&algorithm->hasher,
+	                              &global->buffer->buf[algorithm->offset],
+	                              global->buffer->ready - algorithm->offset);
+	algorithm->offset += r;
+}
+
+
+static void
+finalise(struct algorithm *algorithm, struct global_data *global)
+{
+	if (algorithm->hasher.finalise_const(&algorithm->hasher, &global->buffer->buf[algorithm->offset],
+	                                     global->buffer->ready - algorithm->offset, 0))
+		abort();
+	format_result(algorithm, global->file, global->format, global->hexinput);
+}
+
+
+int
+calculate(const char *file, struct barrier_group *group, struct global_data *global)
+{
+	int fd, is_new_fd, r, ret = -1, saved_errno;
+	const char *fname;
+
+	global->nalgorithms = inithashers(global->algorithms, global->nalgorithms);
+	if (!global->nalgorithms)
+		return 0;
+
+	fd = openfile(file, &is_new_fd, &fname);
+	if (fd < 0)
+		return -1;
+
+	global->buffer->ready = 0;
+	global->buffer->procoff = 0;
+	global->buffer->offset = 0;
+	while (!(r = feedbuffer(fd, global->buffer, fname))) {
+		if (!global->hexinput) {
+			global->buffer->ready = global->buffer->offset;
+			global->buffer->procoff = global->buffer->offset;
+		} else {
+			if (unhex(global->buffer)) {
+				weprintf("%s: not a hexadecimal file", fname);
+				errno = 0;
+				goto fail;
+			}
+		}
+		barriersend(group, global, &process);
+		shiftbuffer(global->algorithms, global->nalgorithms, global->buffer);
+	}
+	if (r < 0)
+		goto fail;
+
+	barriersend(group, global, &finalise);
+	ret = 0;
+fail:
+	saved_errno = errno;
+	destroyhashers(global->algorithms, global->nalgorithms);
+	if (is_new_fd)
+		close(fd);
+	errno = saved_errno;
+	return ret;
+}