feat(cmd): add command_descriptor table and dispatcher

includes/internal/cmd/command.h

@@ -0,0 +1,26 @@
+#ifndef FT_SSL_CMD_COMMAND_H
+#define FT_SSL_CMD_COMMAND_H
+
+#include <stddef.h>
+#include <stdio.h>
+
+#include <cli.h>
+
+enum command_category {
+	CMD_DIGEST,
+	CMD_CIPHER
+};
+
+struct command_descriptor {
+	const char                    *name;
+	enum command_category          category;
+	const struct option_descriptor *opts;
+	size_t                         nb_opts;
+	const void                    *impl;
+	int (*run)(int argc, char **argv, const struct command_descriptor *self);
+};
+
+const struct command_descriptor	*find_command(const char *name);
+void							 print_commands(FILE *out);
+
+#endif

src/cmd/command_table.c

@@ -0,0 +1,54 @@
+#include <stdio.h>
+#include <string.h>
+
+#include <libft_ssl.h>
+
+#include "internal/cmd/command.h"
+#include "internal/cmd/digest_cmd.h"
+
+/* Forward-declare all digest algo globals */
+#define DIGEST_ALGO(lower, ds, bs) extern const struct digest_algo g_##lower;
+#include <digest_algos.h>
+#undef DIGEST_ALGO
+
+static const struct command_descriptor	s_commands[] = {
+	/* Digest commands */
+#define DIGEST_ALGO(lower, ds, bs) \
+	{ #lower, CMD_DIGEST, g_digest_opts, DIGEST_OPT_LEN, &g_##lower, digest_run },
+#include <digest_algos.h>
+#undef DIGEST_ALGO
+	/* Cipher commands (not yet implemented) */
+	{ "base64",  CMD_CIPHER, NULL, 0, NULL, NULL },
+	{ "des",     CMD_CIPHER, NULL, 0, NULL, NULL },
+	{ "des-ecb", CMD_CIPHER, NULL, 0, NULL, NULL },
+	{ "des-cbc", CMD_CIPHER, NULL, 0, NULL, NULL },
+	/* Sentinel */
+	{ NULL, 0, NULL, 0, NULL, NULL }
+};
+
+const struct command_descriptor *
+find_command(const char *name)
+{
+	const struct command_descriptor	*cmd;
+
+	for (cmd = s_commands; NULL != cmd->name; cmd++)
+		if (0 == strcmp(cmd->name, name))
+			return cmd;
+	return NULL;
+}
+
+void
+print_commands(FILE *out)
+{
+	const struct command_descriptor	*cmd;
+
+	fprintf(out, "\nStandard commands:\n");
+	fprintf(out, "\nMessage Digest commands:\n");
+	for (cmd = s_commands; NULL != cmd->name; cmd++)
+		if (CMD_DIGEST == cmd->category)
+			fprintf(out, "  %s\n", cmd->name);
+	fprintf(out, "\nCipher commands:\n");
+	for (cmd = s_commands; NULL != cmd->name; cmd++)
+		if (CMD_CIPHER == cmd->category)
+			fprintf(out, "  %s\n", cmd->name);
+}