Change if-else chain to function table.

kofu.c

@@ -9,50 +9,87 @@
 #include <fcntl.h>
 #include "kocdecl.h"
 
+#define FGETS_BUF_LEN 4096
+#define MAX_COMMAND_ARGS 42
+
+char cmd_buf[FGETS_BUF_LEN];
+
 void prompt() {
     printf("> ");
     fflush(stdout);
 }
 
+bool next_line() {
+    prompt();
+    return fgets(cmd_buf, FGETS_BUF_LEN, stdin) != NULL;
+}
+
+char **split_args(char *s) {
+    int argc = -1;
+    char **argv = (char**)malloc(sizeof(char*) * (MAX_COMMAND_ARGS + 1));
+    char *saveptr;
+    for ( ; (argv[++argc] = strtok_r(s, " \t\n", &saveptr)) != NULL; s = NULL );
+    return argv;
+}
+
+void kofu_ls(char **arg) {
+    void *header = kos_fuse_readdir(arg[1], 0);
+    uint32_t file_cnt = ((uint32_t*)header)[1];
+    printf("file_cnt: %u\n", file_cnt);
+    struct bdfe *kf = header + 0x20;
+    for (; file_cnt > 0; file_cnt--) {
+        printf("%s\n", kf->name);
+        kf++;
+    }
+    return;
+}
+
+void kofu_stat(char **arg) {
+    struct bdfe *kf = kos_fuse_getattr(arg[1]);
+    printf("attr: 0x%2.2x\n", kf->attr);
+    printf("size: %llu\n", kf->size);
+    return;
+}
+
+struct func_table {
+    char *name;
+    void (*func) (char **arg);
+};
+
+struct func_table funcs[] = {
+                              { "ls",   kofu_ls   },
+                              { "stat", kofu_stat },
+                              { NULL,   NULL      },
+                            };
+
 int main(int argc, char **argv) {
     if (argc != 2) {
         printf("usage: kofu <file.xfs>\n");
         exit(1);
     }
 
-    char cmd_buf[4096];
     int fd = open(argv[1], O_RDONLY);
     if (!kos_fuse_init(fd)) {
         exit(1);
     }
-    
+
 //msg_few_args             db 'usage: xfskos image [offset]',0x0a
 //msg_file_not_found       db 'file not found: '
 //msg_unknown_command      db 'unknown command',0x0a
 //msg_not_xfs_partition    db 'not xfs partition',0x0a
-    while(true) {
-        prompt();
-        fgets(cmd_buf, 4095, stdin);
-        int len = strlen(cmd_buf);
-        cmd_buf[len-1] = '\0';
-//        printf("'%s'\n", cmd_buf);
-        if (!strncmp(cmd_buf, "ls ", 3)) {
-            void *header = kos_fuse_readdir(cmd_buf + 4, 0);
-            uint32_t file_cnt = ((uint32_t*)header)[1];
-            printf("file_cnt: %u\n", file_cnt);
-            struct bdfe *kf = header + 0x20;
-            for (; file_cnt > 0; file_cnt--) {
-                printf("%s\n", kf->name);
-                kf++;
+    while(next_line()) {
+        char **arg = split_args(cmd_buf);
+        bool found = false;
+        for (struct func_table *ft = funcs; ft->name != NULL; ft++) {
+            if (!strcmp(arg[0], ft->name)) {
+                ft->func(arg);
+                found = true;
+                break;
             }
-        } else if (!strncmp(cmd_buf, "stat ", 5)) {
-            struct bdfe *kf = kos_fuse_getattr(cmd_buf + 5);
-            printf("attr: 0x%2.2x\n", kf->attr);
-            printf("size: %llu\n", kf->size);
-        } else {
-            printf("unknown command: %s\n", cmd_buf);
+        }
+        if (!found) {
+            printf("unknown command: %s\n", arg[0]);
         }
     }
-
     return 0;
 }