[libakfs] Basic test, headers and functions for the feature

3 files changed, 123 insertions, 5 deletions

diff --git a/c_implementation/include/libakfs.h b/c_implementation/include/libakfs.h
index e31c5ec..83b820e 100644
--- a/c_implementation/include/libakfs.h
+++ b/c_implementation/include/libakfs.h
@@ -21,10 +21,9 @@ typedef struct {
 } sha512sum;
 
 /**
- * This struct describes explicitly the structure of a root_hash. It is the root
- * of a hash merkle tree. Note, that this structure can be used for roots and
- * branches. Possibly, the name will change to something more generic in the
- * future.
+ * This struct describes explicitly the structure of a merkletree_node. Note,
+ * that this structure can be used for roots and branches.
+ *
  * Another note is that instead of approaching this as left and right, as seen
  * in other codebases, we do a head-tail naming. That's because of the BASH
  * implementation that you can find at lib/_ak_fs.
@@ -43,7 +42,7 @@ typedef struct {
      * Hash of tail
      */
     sha512sum tail;
-} root_hash;
+} merkletree_node;
 
 /**
  * This is the current structure of an akfs_map. Due to potential short-comings
@@ -403,5 +402,8 @@ int ak_fs_ls();
  */
 int ak_fs_main(int, char**);
 
+int ak_fs_cat_file_from_root_hash(sha512sum*);
+int ak_fs_cfm(akfs_map_v3*);
+
 #endif // AKFS
 
diff --git a/c_implementation/src/ak_fs.c b/c_implementation/src/ak_fs.c
index 6594f2d..27939bf 100644
--- a/c_implementation/src/ak_fs.c
+++ b/c_implementation/src/ak_fs.c
@@ -278,3 +278,101 @@ int ak_fs_ls()
     ak_fs_maps_v3_print_bif(&maps_ptr, len);
     return 0;
 }
+
+int ak_fs_root_hash_resolve(merkletree_node *h)
+{
+    const char* leafs_dir = getenv("AK_LEAFSDIR");
+    FILE *fd;
+    char *fullpath;
+    asprintf(&fullpath, "%s/%s", leafs_dir, ak_fs_sha512sum_struct_read_as_string(&h->head));
+    fd = fopen(fullpath, "r");
+    if ( fd == NULL )
+    {
+        perror("fopen");
+        return 1;
+    }
+    char buffer[258];
+    fread(&buffer, sizeof(buffer), 1, fd);
+    fclose(fd);
+    char h1[129] = {0};
+    char h2[129] = {0};
+    if ( buffer[128] == '\n' && buffer[257] == '\n' ) printf("\\n found on the expected spot!\n");
+    merkletree_node h0;
+    ak_fs_sha512sum_init(&h0.root);
+    ak_fs_sha512sum_init(&h0.head);
+    ak_fs_sha512sum_init(&h0.tail);
+    h0.root = h->root;
+    for( size_t i = 0; i < 128; ++i )
+    {
+        h1[i] = buffer[i];
+    }
+    h1[128] = '\0';
+    for( size_t i = 0; i < 128; ++i )
+    {
+        h2[i] = buffer[i+129];
+    }
+    h2[128] = '\0';
+    ak_fs_sha512sum_string_to_struct(h1, &h0.head);
+    ak_fs_sha512sum_string_to_struct(h2, &h0.tail);
+    ak_fs_root_hash_resolve(&h0);
+
+    return 0;
+}
+
+int ak_fs_cat_file_from_root_hash(sha512sum* rh)
+{
+    printf("%s: %s\n", __func__, getenv("AK_CHUNKSDIR"));
+    const char* leafs_dir = getenv("AK_LEAFSDIR");
+    // We always expect root hash to be in the AK_LEAFSDIR directory, however it
+    // might as well not be there
+    FILE *fd;
+    // We need to join the root_hash with the directory first
+    char *fullpath;
+    asprintf(&fullpath, "%s/%s", leafs_dir, ak_fs_sha512sum_struct_read_as_string(rh));
+    fd = fopen(fullpath, "r");
+    if ( fd == NULL )
+    {
+        perror("fopen");
+        return 1;
+    }
+    char buffer[258];
+    fread(&buffer, sizeof(buffer), 1, fd);
+    fclose(fd);
+    char h1[129] = {0};
+    char h2[129] = {0};
+    if ( buffer[128] == '\n' && buffer[257] == '\n' ) printf("\\n found on the expected spot!\n");
+    merkletree_node h0;
+    ak_fs_sha512sum_init(&h0.root);
+    ak_fs_sha512sum_init(&h0.head);
+    ak_fs_sha512sum_init(&h0.tail);
+    h0.root = *rh;
+    for( size_t i = 0; i < 128; ++i )
+    {
+        h1[i] = buffer[i];
+    }
+    h1[128] = '\0';
+    for( size_t i = 0; i < 128; ++i )
+    {
+        h2[i] = buffer[i+129];
+    }
+    h2[128] = '\0';
+    ak_fs_sha512sum_string_to_struct(h1, &h0.head);
+    ak_fs_sha512sum_string_to_struct(h2, &h0.tail);
+    ak_fs_root_hash_resolve(&h0);
+    // ak_log_debug(__func__, ak_fs_sha512sum_struct_read_as_string(&h0.root));
+    // ak_log_debug(__func__, ak_fs_sha512sum_struct_read_as_string(&h0.head));
+    // ak_log_debug(__func__, ak_fs_sha512sum_struct_read_as_string(&h0.tail));
+    // if ( ak_fs_verify_input_is_hash(h1, strlen(h1))) printf("head:\n%s\n---\n", h1);
+    // if ( ak_fs_verify_input_is_hash(h2, strlen(h2))) printf("tail:\n%s\n---\n", h2);
+    return 0;
+}
+
+int ak_fs_cfm(akfs_map_v3* map)
+{
+    sha512sum x;
+    ak_fs_sha512sum_init(&x);
+    x = *(ak_fs_map_v3_get_root_hash(map));
+    // printf("%s\n", ak_fs_sha512sum_struct_read_as_string(&x));
+    ak_fs_cat_file_from_root_hash(&x);
+    return 0;
+}
diff --git a/c_implementation/tests/test_akfs.c b/c_implementation/tests/test_akfs.c
index 55607c4..247a59a 100644
--- a/c_implementation/tests/test_akfs.c
+++ b/c_implementation/tests/test_akfs.c
@@ -241,6 +241,21 @@ static void test_ak_fs_ls()
     ak_fs_ls();
 }
 
+static void test_ak_fs_cfm()
+{
+    ak_log_test(__func__, ".....=====.....");
+    akfs_map_v3 map;
+    ak_fs_map_v3_init(&map);
+    char *map_string = "28bde5fa7aacd8da0ec84b61cf3a69141686906c00f8cff904c9a0b12f5a4cf061da254feb188c32b711b2e1d6a3853d5ac3fb0bcd3564899bae55dd30470392";
+    ak_fs_sha512sum_string_to_struct(map_string, &(map.mh));
+    if ( ak_fs_map_v3_open_from_file(&map) != 0 )
+    {
+        ak_log_debug(__func__, "FAILED");
+        return;
+    }
+    ak_fs_cfm(&map);
+}
+
 
 int main(void)
 {
@@ -279,5 +294,8 @@ int main(void)
     printf("%lu\n", (unsigned long)sizeof(sha512sum));
     printf("%lu\n", (unsigned long)sizeof(akfs_map_v3));
     printf("%lu\n", (unsigned long)sizeof(akfs_map_v4));
+
+    // Test ak_fs_cfm
+    test_ak_fs_cfm();
     return 0;
 }