get files in FS by their hash number

TODO.md

@@ -2,12 +2,12 @@
 
 ## Features
 
-- [ ] Database integration
+- [x] Database integration
 - [ ] Paging in the file list
-- [ ] Get files in FS by their hash
+- [x] Get files in FS by their hash
 - [ ] Registration
 - [ ] Message to admin
-- [ ] Advanced folder structure for the storage
+- [x] Advanced folder structure in the storage
 - [ ] File encryption
 - [ ] Connection encryption
 

src/db.c

@@ -54,6 +54,15 @@ static int exit_query_2(int code) {
   return code;
 }
 
+static void *exit_query_3(void *ptr) {
+  fprintf(stderr, "%s\n", PQerrorMessage(conn));
+
+  if (res != NULL)
+    PQclear(res);
+
+  return ptr;
+}
+
 static void processNotice(void *arg, const char *message) {
   UNUSED(arg);
   UNUSED(message);
@@ -104,20 +113,18 @@ int db_user_auth(i_auth_t *credentials, o_auth_t *response) {
   return exit_query(2);
 }
 
-int db_save_collision(uint32_t hash);
-
 #define BIN 1
 #define TEXT 0
 
-int db_save_file(session *s) {
+int32_t db_save_file(session *s) {
   const char *paramValues[6];
   int paramFormats[6];
   int paramLengths[6];
   int collision_id = 0;
-  session_file *sf = s->file;
+  s_file_t *sf = s->file;
 
   int32_t uid_n = htonl(s->uid);
-  int64_t size_n = htonl(sf->size);
+  uint64_t size_n = htobe64(sf->size);
   int32_t hash_n = htonl(sf->hash);
   int32_t perm_n = htonl(sf->permissions);
 
@@ -130,7 +137,7 @@ int db_save_file(session *s) {
 
   paramLengths[0] = sizeof(int32_t);
   paramLengths[1] = strlen(sf->name);
-  paramLengths[2] = sizeof(int64_t);
+  paramLengths[2] = sizeof(uint64_t);
   paramLengths[3] = sizeof(int32_t);
   paramLengths[4] = strlen(sf->description);
   paramLengths[5] = sizeof(int32_t);
@@ -158,9 +165,57 @@ int db_save_file(session *s) {
 }
 
 // TODO: get file
-// int db_get_file(i_get_file_db *arg) {
+s_file_t *db_get_file(i_get_file_db *arg) {
+  s_file_t *sf;
+  char s_field[24];
+  char value[64] = "";
+  const char *paramValues[1];
+  char query[512];
+  uint32_t q_len = 0;
 
-// }
+  if (arg->id) {
+    strcpy(s_field, "id");
+    sprintf(value, "%u", arg->id);
+  } else if (strlen(arg->name)) {
+    strcpy(s_field, "name");
+    strcpy(value, arg->name);
+  } else if (arg->user_id) {
+    strcpy(s_field, "user_id");
+    sprintf(value, "%u", arg->user_id);
+  } else {
+    fprintf(stderr, "db_get_file: none of the args is specified!\n");
+    return NULL;
+  }
+
+  paramValues[0] = value;
+
+  sprintf(query,
+          "SELECT files.id, user_id, name, size, description, permissions, hash "
+          "FROM files JOIN users ON user_id = users.id WHERE files.%s = $1%n",
+          s_field, &q_len);
+
+  res = PQexecParams(conn, query, 1, NULL, paramValues, NULL, NULL, TEXT);
+
+  if (PQresultStatus(res) != PGRES_TUPLES_OK && !PQntuples(res))
+    return exit_query_3(NULL);
+
+  sf = malloc(sizeof(s_file_t));
+  sf->id = atoi(PQgetvalue(res, 0, 0));
+  sf->owner_id = atoi(PQgetvalue(res, 0, 1));
+  char *name = PQgetvalue(res, 0, 2);
+  sf->name = malloc(strlen(name) + 1);
+  strcpy(sf->name, name);
+  sf->size = atoll(PQgetvalue(res, 0, 3));
+  char *description = PQgetvalue(res, 0, 4);
+  sf->description = malloc(strlen(description) + 1);
+  strcpy(sf->description, description);
+  sf->permissions = atoi(PQgetvalue(res, 0, 5));
+  sf->hash = atoi(PQgetvalue(res, 0, 6));
+
+  clearRes();
+
+  return sf;
+}
 
 uint64_t db_get_files_data(i_get_files_db *arg, fl_t **fl_start,
                            uint64_t *full_count) {
@@ -204,12 +259,12 @@ uint64_t db_get_files_data(i_get_files_db *arg, fl_t **fl_start,
   paramFormats[0] = BIN;
   paramFormats[1] = BIN;
 
-  sprintf(
-      query,
-      "SELECT user_id, name, size, description, permissions, hash, username "
-      "FROM files JOIN users ON user_id = users.id "
-      "ORDER BY files.%s %s LIMIT $1 OFFSET $2",
-      sort_by, sort_dir);
+  sprintf(query,
+          "SELECT files.id, user_id, name, size, description, permissions, "
+          "hash, username "
+          "FROM files JOIN users ON user_id = users.id "
+          "ORDER BY files.%s %s LIMIT $1 OFFSET $2",
+          sort_by, sort_dir);
 
   res = PQexecParams(conn, query, 2, NULL, paramValues, paramLengths,
                      paramFormats, TEXT);
@@ -220,17 +275,18 @@ uint64_t db_get_files_data(i_get_files_db *arg, fl_t **fl_start,
   for (i = 0; i < PQntuples(res); i++) {
     fl_t *l_item = malloc(sizeof(fl_t));
     l_item->next = NULL;
-    l_item->owner_id = atoi(PQgetvalue(res, i, 0));
-    char *name = PQgetvalue(res, i, 1);
+    l_item->id = atoi(PQgetvalue(res, i, 0));
+    l_item->owner_id = atoi(PQgetvalue(res, i, 1));
+    char *name = PQgetvalue(res, i, 2);
     l_item->name = malloc(strlen(name) + 1);
     strcpy(l_item->name, name);
-    l_item->size = atoll(PQgetvalue(res, i, 2));
-    char *description = PQgetvalue(res, i, 3);
+    l_item->size = atoll(PQgetvalue(res, i, 3));
+    char *description = PQgetvalue(res, i, 4);
     l_item->description = malloc(strlen(description) + 1);
     strcpy(l_item->description, description);
-    l_item->permissions = atoi(PQgetvalue(res, i, 4));
-    l_item->hash = atoi(PQgetvalue(res, i, 5));
-    char *owner = PQgetvalue(res, i, 6);
+    l_item->permissions = atoi(PQgetvalue(res, i, 5));
+    l_item->hash = atoi(PQgetvalue(res, i, 6));
+    char *owner = PQgetvalue(res, i, 7);
     l_item->owner = malloc(strlen(owner) + 1);
     strcpy(l_item->owner, owner);
 

src/db.h

@@ -18,9 +18,9 @@ typedef struct {
 /* Get file */
 
 typedef struct {
-  int id;
-  char *name;
-  int user_id;
+  uint32_t id;
+  uint32_t user_id;
+  char name[64];
 } i_get_file_db;
 
 enum sort_direction { ASC, DESC };
@@ -35,9 +35,10 @@ typedef struct {
   enum sort_direction sort_direction;
 } i_get_files_db;
 
-int init_db_connection();
-int db_user_auth(i_auth_t *credentials, o_auth_t *response);
-int db_save_file(session *s);
+int32_t init_db_connection();
+int32_t db_save_file(session *s);
+int32_t db_user_auth(i_auth_t *credentials, o_auth_t *response);
+s_file_t *db_get_file(i_get_file_db *arg);
 uint64_t db_get_files_data(i_get_files_db *arg, fl_t **fl_start,
                            uint64_t *full_count);
 #endif

src/file_p.c

@@ -100,43 +100,10 @@ void file_list(session *sess, server_data_t *s_d) {
   } while ((fl_current = fl_current->next) != NULL);
 
   sess->fl_start = fl_start;
-  write(sess->sd, list_end, sizeof(list_end));
+  write(sess->sd, list_end, sizeof(list_end)-1);
   write(sess->sd, page_info, strlen(page_info));
 }
 
-int file_send_prepare(session *sess, char *line, server_data_t *s_d) {
-  sess->file = malloc(sizeof(session_file));
-  int sd = sess->sd;
-  char fname[50];
-  sscanf(line, "%*s %*s %s", fname);
-  char filepath[256];
-  sprintf(filepath, "%s/%s", STORAGE_FOLDER, fname);
-  char st_message[256];
-  size_t fsize;
-
-  int file_d = open(filepath, O_RDONLY);
-
-  if (file_d == -1) {
-    fprintf(stdout, "ERROR: %d\n", errno);
-    char err_mes[256];
-    int mlen;
-    mlen = sprintf(err_mes, "Can't open file named \"%s\"\n", fname);
-    write(sd, err_mes, mlen);
-    return -1;
-  }
-
-  fsize = lseek(file_d, 0, SEEK_END);
-  lseek(file_d, 0, SEEK_SET);
-
-  sess->file->size = fsize;
-  sess->file->rest = fsize;
-  sess->file->name = malloc(strlen(fname));
-  int fname_len = strlen(fname) - 1;
-  strncpy(sess->file->name, fname, fname_len);
-  sess->file->name[fname_len] = 0;
-  return 0;
-}
-
 int directory_exists(const char *path) {
   struct stat info;
 
@@ -156,13 +123,58 @@ void extract_names_from_hash(uint32_t file_hash, char *dirname, char *fname) {
   fname[6] = 0;
 }
 
+int32_t file_send_prepare(session *sess, char *line, server_data_t *s_d) {
+  int32_t sd = sess->sd;
+  i_get_file_db args = {.id = 0, .user_id = 0, .name = ""};
+  char st_message[256];
+  int32_t file_d;
+  size_t fsize;
+  char hashed_dir_name[3];
+  char hashed_name[7];
+  char err_mes[256];
+  uint32_t mlen;
+
+  sscanf(line, "%*s %*s %s", args.name);
+  sess->file = db_get_file(&args);
+
+  if (sess->file == NULL)
+    return -1;
+
+  extract_names_from_hash(sess->file->hash, hashed_dir_name, hashed_name);
+  sess->file->path = malloc(sizeof(STORAGE_FOLDER) + 2 + 9);
+  sprintf(sess->file->path, "%s/%s/%s", STORAGE_FOLDER, hashed_dir_name,
+          hashed_name);
+
+  file_d = open(sess->file->path, O_RDONLY);
+
+  if (file_d == -1) {
+    fprintf(stdout, "ERROR: %d\n", errno);
+    mlen = sprintf(err_mes, "Can't open file with id = %u\n", sess->file->id);
+    write(sd, err_mes, mlen);
+    return -2;
+  }
+
+  fsize = lseek(file_d, 0, SEEK_END);
+  lseek(file_d, 0, SEEK_SET);
+
+  if (sess->file->size != fsize) {
+    mlen = sprintf(err_mes, "File with id = %u exists, but seems to be damaged\n", sess->file->id);
+    write(sd, err_mes, mlen);
+    return -3;
+  }
+
+  sess->file->rest = fsize;
+  sess->fd = file_d;
+  return 0;
+}
+
 int file_receive_prepare(session *sess, char *line, server_data_t *s_d) {
   int sd = sess->sd;
   char fname[64];
   size_t fsize;
   int perm;
   sscanf(line, "file upload \"%s %zd %d", fname, &fsize, &perm);
-  sess->file = malloc(sizeof(session_file));
+  sess->file = malloc(sizeof(s_file_t));
   sess->file->name = malloc(sizeof(char) * strlen(fname));
   sess->file->path = malloc(sizeof(STORAGE_FOLDER) + 2 + 9);
   sess->file->permissions = (char)perm;
@@ -235,7 +247,7 @@ int file_receive_prepare(session *sess, char *line, server_data_t *s_d) {
 }
 
 void clear_file_from_sess(session *s) {
-  session_file *sf = s->file;
+  s_file_t *sf = s->file;
   if (sf->name != NULL) {
     free(sf->name);
     sf->name = NULL;

src/main.h

@@ -49,7 +49,9 @@ typedef struct {
   size_t size;
   size_t rest;
   uint32_t hash;
-} session_file;
+  uint32_t id;
+  uint32_t owner_id;
+} s_file_t;
 
 typedef struct fl_t {
   char *name;
@@ -59,6 +61,7 @@ typedef struct fl_t {
   uint32_t owner_id;
   uint32_t hash;
   size_t size;
+  uint32_t id;
   struct fl_t *next;
 } fl_t;
 
@@ -74,7 +77,7 @@ typedef struct session {
   uint32_t uid;
   int fd;
   int sd; /* session descriptor */
-  session_file *file;
+  s_file_t *file;
   fl_t *fl_start;
   fl_t *fl_current;
 } session;