Merge pull request #9 from voidbert/voidbert-fixes

Generic fixes

trabalho-pratico/include/utils/dataset_parser.h

@@ -69,7 +69,7 @@
  *     person_dataset_t *dataset = (person_dataset_t *) user_data;
  *
  *     // Copy string to another buffer, as it will be destroyed when the next line is parsed
- *     char *name_copy              = string_duplicate(token);
+ *     char *name_copy              = strdup(token);
  *     dataset->current_person.name = name_copy;
  *     return 0;
  * }
@@ -92,6 +92,13 @@
  *     return 0;
  * }
  *
+ * // Print line before parsing (debug purposes)
+ * int before_parse_token(void *user_data, char *token) {
+ *     (void) user_data;
+ *     printf("Parsing line: %s\n", token);
+ *     return 0;
+ * }
+ *
  * // Gets called once for line, when each line is done parsing
  * int add_to_reject_from_database(void *user_data, int retcode) {
  *     person_dataset_t *dataset = (person_dataset_t *) user_data;
@@ -127,7 +134,10 @@
  *     fixed_n_delimiter_parser_grammar_t      *token_grammar =
  *         fixed_n_delimiter_parser_grammar_new(';', 3, token_grammar_callbacks);
  *     dataset_parser_grammar_t *grammar =
- *         dataset_parser_grammar_new('\n', token_grammar, add_to_reject_from_database);
+ *         dataset_parser_grammar_new('\n',
+ *                                    token_grammar,
+ *                                    before_parse_token,
+ *                                    add_to_reject_from_database);
  *
  *     person_dataset_t dataset = {0};
  *     int parse_result = dataset_parser_parse(file, grammar, &dataset);
@@ -184,6 +194,21 @@
  */
 typedef struct dataset_parser_grammar_t dataset_parser_grammar_t;
 
+/**
+ * @brief   Callback for each token delimited by the first-order delimiter in a dataset parser
+ *          (e.g.: CSV line).
+ * @details This is called before each token is parsed by ::fixed_n_delimiter_parser_parse_string.
+ *
+ * @param user_data Pointer provided to ::dataset_parser_parse, so that this callback can modify
+ *                  the program's state.
+ * @param unparsed  Token to be parsed.
+ *
+ * @return `0` on success, other value for immediate termination of parsing. It's recommeneded that
+ *         these values are positive, as negative values have special meanings (see
+ *         ::DATASET_PARSER_PARSE_RET_ALLOCATION_FAILURE).
+ */
+typedef int (*dataset_parser_token_before_parse_callback)(void *user_data, char *unparsed);
+
 /**
  * @brief   Callback for each token delimited by the first-order delimiter in a dataset parser
  *          (e.g.: CSV line).
@@ -208,6 +233,7 @@ typedef int (*dataset_parser_token_callback)(void *user_data, int retcode);
  * @param token_grammar         Grammar for ::fixed_n_delimiter_parser_parse_string, used to parse
  *                              each token delimited by @p first_order_delimiter. Ownership of this
  *                              value will be taken by this function.
+ * @param before_parse_callback Callback called before parsing each token.
  * @param token_callback        Callback called after processing each token with @p token_grammar.
  *
  * @return `malloc`-allocated ::dataset_parser_grammar_t (or `NULL` on allocation failure). This
@@ -218,9 +244,10 @@ typedef int (*dataset_parser_token_callback)(void *user_data, int retcode);
  * See [the header file's documentation](@ref dataset_parser_examples).
  */
 dataset_parser_grammar_t *
-    dataset_parser_grammar_new(char                                first_order_delimiter,
-                               fixed_n_delimiter_parser_grammar_t *token_grammar,
-                               dataset_parser_token_callback       token_callback);
+    dataset_parser_grammar_new(char                                       first_order_delimiter,
+                               fixed_n_delimiter_parser_grammar_t        *token_grammar,
+                               dataset_parser_token_before_parse_callback before_parse_callback,
+                               dataset_parser_token_callback              token_callback);
 
 /**
  * @brief Frees memory allocated by ::dataset_parser_grammar_new.

trabalho-pratico/include/utils/date.h

@@ -100,7 +100,7 @@ int date_from_values(date_t *output, uint16_t year, uint8_t month, uint8_t day);
  * @brief Parses a **MODIFIABLE** string containing a date.
  *
  * @param output Where the parsed date is placed. Won't be modified on failure.
- * @param input  String to parse, that will be modified. Must be in the format `"YYYY/MM/DD"`.
+ * @param input  String to parse, that won't be modified. Must be in the format `"YYYY/MM/DD"`.
  *
  * @retval 0 Parsing success.
  * @retval 1 Parsing failure.

trabalho-pratico/include/utils/date_and_time.h

@@ -75,7 +75,7 @@ void date_and_time_from_values(date_and_time_t *output, date_t date, daytime_t t
  * @brief Parses a **MODIFIABLE** string containing a date and a time.
  *
  * @param output Where the parsed timed date is placed. Won't be modified on failure.
- * @param input  String to parse, that will be modified. Must be in the format
+ * @param input  String to parse, that won't be modified. Must be in the format
  *               `"YYYY/MM/DD HH:MM:SS"`.
  *
  * @retval 0 Parsing success.

trabalho-pratico/include/utils/daytime.h

@@ -89,7 +89,7 @@ int daytime_from_values(daytime_t *output, uint8_t hours, uint8_t minutes, uint8
  * @brief Parses a **MODIFIABLE** string containing a time.
  *
  * @param output Where the parsed time is placed. Won't be modified on failure.
- * @param input  String to parse, that will be modified. Must be in the format `"HH:MM:SS"`.
+ * @param input  String to parse, that won't be modified. Must be in the format `"HH:MM:SS"`.
  *
  * @retval 0 Parsing success.
  * @retval 1 Parsing failure.

trabalho-pratico/include/utils/fixed_n_delimiter_parser.h

@@ -43,7 +43,7 @@
  *     (void) ntoken;
  *
  *     // Copy string to another buffer
- *     char *name_copy = string_duplicate(token); // No failure check in this example
+ *     char *name_copy = strdup(token); // No failure check in this example
  *     ((person_t *) user_data)->name = name_copy;
  *     return 0;
  * }
@@ -201,7 +201,8 @@ void fixed_n_delimiter_parser_grammar_free(fixed_n_delimiter_parser_grammar_t *g
 /**
  * @brief Parses a **MODIFIABLE** string using a parser defined by @p grammar.
  *
- * @param input     String to parse, that that will be modified for this function to work.
+ * @param input     String to parse, that that will be modified for this function to work, but then
+ *                  restored to its original form.
  * @param grammar   Grammar that defines the parser to be used.
  * @param user_data Pointer passed to every callback in @p grammar, so that they can edit the
  *                  program's state.

trabalho-pratico/include/utils/string_utils.h

@@ -83,13 +83,6 @@
 #ifndef STRING_UTILS_H
 #define STRING_UTILS_H
 
-/**
- * @brief Allocates a temporary buffer for @p input and copies @p input there.
- * @param Input to be duplicated.
- * @return A buffer owned by the caller (`NULL` on failure).
- */
-char *string_duplicate(const char *input);
-
 /**
  * @brief Callback method for ::string_tokenize, called for every token read.
  *
@@ -106,7 +99,8 @@ typedef int (*tokenize_iter_callback_t)(void *user_data, char *token);
 /**
  * @brief Splits a **MODIFIABLE** string into tokens, separated by @p delimiter.
  *
- * @param input     String to tokenize, that that will be modified for this function to work.
+ * @param input     String to tokenize, that that will be modified for this function to work, but
+ *                  later restored to its original form.
  * @param delimiter Character to separate tokens. It won't be part of those tokens.
  * @param callback  Function called for every token read.
  * @param user_data Pointer passed to every call of @p callback, so that it can edit program state.

trabalho-pratico/reports/relatorio-fase1.tex

@@ -40,9 +40,14 @@ \section{Otimização do uso de memória}
 quantidade de memória utilizada, de modo não sermos futuramente obrigados a reescrever partes
 significativas do nosso código.
 
-\subsection{Observação do \emph{dataset}}
-
-TODO - como usámos tipos que não strings nas entidades por observação do \emph{dataset}.
+\subsection{Observação do \emph{dataset} e das \emph{queries}}
+
+Pudemos observar que alguns campos do \emph{dataset} nunca precisavam de estar presentes no
+\emph{output} de nenhuma \emph{query} (ex: o \emph{email} de um utilizador), pelo que era escusado
+o seu armazenamento na base de dados, sendo apenas necessária a sua validação durante o
+\emph{parsing}. Ademais, por observação dos \emph{datasets} em si, pudemos concluir que é possível
+armazenar certos campos como estruturas de dados mais compactas (ex: o identificador de um voo
+pode ser armazenado como um inteiro, em vez de uma \emph{string}).
 
 \subsection{Tipos opacos}
 

trabalho-pratico/src/utils/dataset_parser.c

@@ -34,15 +34,18 @@
  *
  * @var dataset_parser_grammar_t::token_grammar
  *     @brief Grammar to use to parse single tokens with ::fixed_n_delimiter_parser_parse_string.
+ * @var dataset_parser_grammar_t::before_parse_callback
+ *     @brief Callback called before parsing each token.
  * @var dataset_parser_grammar_t::token_callback
  *     @brief Callback called after processing each token.
  * @var dataset_parser_grammar_t::delimiter
  *     @brief Separator between first-order tokens (e.g.: ``'\n'`` for CSV files).
  */
 struct dataset_parser_grammar_t {
-    fixed_n_delimiter_parser_grammar_t *token_grammar;
-    dataset_parser_token_callback       token_callback;
-    char                                delimiter;
+    fixed_n_delimiter_parser_grammar_t        *token_grammar;
+    dataset_parser_token_before_parse_callback before_parse_callback;
+    dataset_parser_token_callback              token_callback;
+    char                                       delimiter;
 };
 
 /**
@@ -65,18 +68,20 @@ typedef struct {
 } dataset_parser_t;
 
 dataset_parser_grammar_t *
-    dataset_parser_grammar_new(char                                first_order_delimiter,
-                               fixed_n_delimiter_parser_grammar_t *token_grammar,
-                               dataset_parser_token_callback       token_callback) {
+    dataset_parser_grammar_new(char                                       first_order_delimiter,
+                               fixed_n_delimiter_parser_grammar_t        *token_grammar,
+                               dataset_parser_token_before_parse_callback before_parse_callback,
+                               dataset_parser_token_callback              token_callback) {
 
     dataset_parser_grammar_t *grammar = malloc(sizeof(struct dataset_parser_grammar_t));
     if (!grammar) {
         return NULL;
     }
 
-    grammar->delimiter      = first_order_delimiter;
-    grammar->token_grammar  = token_grammar;
-    grammar->token_callback = token_callback;
+    grammar->delimiter             = first_order_delimiter;
+    grammar->token_grammar         = token_grammar;
+    grammar->before_parse_callback = before_parse_callback;
+    grammar->token_callback        = token_callback;
 
     return grammar;
 }
@@ -102,6 +107,10 @@ int __parse_stream_iter(void *user_data, char *token) {
         return 0;
     }
 
+    int before_parse_ret = parser->grammar->before_parse_callback(parser->user_data, token);
+    if (before_parse_ret)
+        return before_parse_ret;
+
     int parser_ret = fixed_n_delimiter_parser_parse_string(token,
                                                            parser->grammar->token_grammar,
                                                            parser->user_data);

trabalho-pratico/src/utils/date.c

@@ -34,8 +34,6 @@
 /**
  * @brief Grammar for parsing dates.
  * @details Shall not be modified apart from its creation.
- *
- * TODO - ask professors if we can use global variables
  */
 fixed_n_delimiter_parser_grammar_t *date_grammar = NULL;
 
@@ -152,7 +150,7 @@ int date_from_string(date_t *output, char *input) {
 }
 
 int date_from_string_const(date_t *output, const char *input) {
-    char *buffer = string_duplicate(input);
+    char *buffer = strdup(input);
     if (!buffer)
         return 1;
 

trabalho-pratico/src/utils/date_and_time.c

@@ -35,8 +35,6 @@
 /**
  * @brief Grammar for parsing timed dates.
  * @details Shall not be modified apart from its creation.
- *
- * TODO - ask professors if we can use global variables
  */
 fixed_n_delimiter_parser_grammar_t *date_and_time_grammar = NULL;
 
@@ -115,7 +113,7 @@ int date_and_time_from_string(date_and_time_t *output, char *input) {
 }
 
 int date_and_time_from_string_const(date_and_time_t *output, const char *input) {
-    char *buffer = string_duplicate(input);
+    char *buffer = strdup(input);
     if (!buffer)
         return 1;
 

trabalho-pratico/src/utils/daytime.c

@@ -34,8 +34,6 @@
 /**
  * @brief Grammar for parsing times.
  * @details Shall not be modified apart from its creation.
- *
- * TODO - ask professors if we can use global variables
  */
 fixed_n_delimiter_parser_grammar_t *daytime_grammar = NULL;
 
@@ -130,7 +128,7 @@ int daytime_from_string(daytime_t *output, char *input) {
 }
 
 int daytime_from_string_const(daytime_t *output, const char *input) {
-    char *buffer = string_duplicate(input);
+    char *buffer = strdup(input);
     if (!buffer)
         return 1;
 

trabalho-pratico/src/utils/fixed_n_delimiter_parser.c

@@ -151,7 +151,7 @@ int fixed_n_delimiter_parser_parse_string(char                               *in
 int fixed_n_delimiter_parser_parse_string_const(const char                         *input,
                                                 fixed_n_delimiter_parser_grammar_t *grammar,
                                                 void                               *user_data) {
-    char *buffer = string_duplicate(input);
+    char *buffer = strdup(input);
     if (!buffer)
         return FIXED_N_DELIMITER_PARSER_PARSE_STRING_CONST_RET_MALLOC_FAILURE;
 

trabalho-pratico/src/utils/string_utils.c

@@ -32,16 +32,6 @@
 
 #include "utils/string_utils.h"
 
-char *string_duplicate(const char *input) {
-    size_t buffer_size = strlen(input) + 1;
-    char  *buffer      = malloc(buffer_size);
-    if (!buffer)
-        return NULL;
-
-    (void) memcpy(buffer, input, buffer_size);
-    return buffer;
-}
-
 int string_tokenize(char                    *input,
                     char                     delimiter,
                     tokenize_iter_callback_t callback,
@@ -54,6 +44,9 @@ int string_tokenize(char                    *input,
         int cb_result = callback(user_data, token);
         if (cb_result)
             return cb_result;
+
+        if (input)
+            *(input - 1) = delimiter; /* Restore string */
     }
 
     return 0;
@@ -64,7 +57,7 @@ int string_const_tokenize(const char              *input,
                           tokenize_iter_callback_t callback,
                           void                    *user_data) {
 
-    char *buffer = string_duplicate(input);
+    char *buffer = strdup(input);
     if (!buffer)
         return STRING_CONST_TOKENIZE_FAILED_MALLOC;