core: Add initial state management

Signed-off-by: Ian Moffett <ian@mirocom.org>

core/rifle.c

@@ -1,6 +1,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include "rifle/state.h"
 
 /* Compiler version */
 #define RIFLE_VERSION "0.0.1"
@@ -28,9 +29,23 @@ version(void)
     );
 }
 
+static int
+compile(const char *in_path)
+{
+    struct rifle_state state;
+
+    if (rifle_state_init(&state, in_path) < 0) {
+        return -1;
+    }
+
+    rifle_state_destroy(&state);
+    return 0;
+}
+
 int
 main(int argc, char **argv)
 {
+    size_t files_compiled = 0;
     int opt;
 
     /* Begin parsing command line options */
@@ -45,5 +60,17 @@ main(int argc, char **argv)
         }
     }
 
+    while (optind < argc) {
+        if (compile(argv[optind++]) < 0) {
+            break;
+        }
+
+        ++files_compiled;
+    }
+
+    if (files_compiled == 0) {
+        printf("fatal: no input files\n");
+        return -1;
+    }
     return 0;
 }

core/state.c

@@ -0,0 +1,29 @@
+#include <fcntl.h>
+#include <unistd.h>
+#include "rifle/state.h"
+
+int
+rifle_state_init(struct rifle_state *state, const char *in_path)
+{
+    if (state == NULL || in_path == NULL) {
+        return -1;
+    }
+
+    state->in_fd = open(in_path, O_RDONLY);
+    if (state->in_fd < 0) {
+        return -1;
+    }
+
+    return 0;
+}
+
+void
+rifle_state_destroy(struct rifle_state *state)
+{
+    if (state == NULL) {
+        return;
+    }
+
+    close(state->in_fd);
+    state->in_fd = -1;
+}

inc/rifle/state.h

@@ -0,0 +1,35 @@
+#ifndef RIFLE_STATE_H
+#define RIFLE_STATE_H 1
+
+#include <stdint.h>
+#include <stddef.h>
+
+/*
+ * Represents the compiler state
+ *
+ * @in_fd: Input file descriptor
+ * @line_num: Current line number
+ */
+struct rifle_state {
+    int in_fd;
+    size_t line_num;
+};
+
+/*
+ * Initialize the compiler state
+ *
+ * @state: State to initialize
+ * @in_path: Input path
+ *
+ * Returns zero on success
+ */
+int rifle_state_init(struct rifle_state *state, const char *in_path);
+
+/*
+ * Destroy the compiler state
+ *
+ * @state: Compiler state to destroy
+ */
+void rifle_state_destroy(struct rifle_state *state);
+
+#endif  /* !RIFLE_STATE_H */