From: Jeremy Tan Date: Thu, 12 Sep 2013 14:06:26 +0000 (+0800) Subject: Add request parsing helper, add TIMEVAL_* macros, move timestamps to identify module X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=a0c96fa8feb1938db84d95b14c320e6c7511c282;p=matches%2FMCTX3420.git Add request parsing helper, add TIMEVAL_* macros, move timestamps to identify module --- diff --git a/server/common.h b/server/common.h index 1275032..c2edd3d 100644 --- a/server/common.h +++ b/server/common.h @@ -28,4 +28,9 @@ #include "fastcgi.h" #include "thread.h" +/**Converts a timeval to a double**/ +#define TIMEVAL_TO_DOUBLE(tv) ((tv).tv_sec + 1e-6 * ((tv).tv_usec)) +/**Takes the tv1-tv2 between two timevals and returns the result as a double*/ +#define TIMEVAL_DIFF(tv1, tv2) ((tv1).tv_sec - (tv2).tv_sec + 1e-6 * ((tv1).tv_usec - (tv2).tv_usec)) + #endif //_COMMON_H diff --git a/server/fastcgi.c b/server/fastcgi.c index e41e375..8c6355a 100644 --- a/server/fastcgi.c +++ b/server/fastcgi.c @@ -8,6 +8,7 @@ #include #include +#include #include "common.h" #include "sensor.h" @@ -37,23 +38,38 @@ struct FCGIContext { * @param params User specified paramters: [actuators, sensors] */ static void IdentifyHandler(FCGIContext *context, char *params) { - bool identSensors = false, identActuators = false; - const char *key, *value; + bool ident_sensors = false, ident_actuators = false; + //const char *key, *value; + struct timeval now; int i; - while ((params = FCGI_KeyPair(params, &key, &value))) { + FCGIValue values[2] = {{"sensors", &ident_sensors, FCGI_BOOL_T}, + {"actuators", &ident_actuators, FCGI_BOOL_T}}; + + if (!FCGI_ParseRequest(context, params, values, 2)) + return; + + /*while ((params = FCGI_KeyPair(params, &key, &value))) { if (!strcmp(key, "sensors")) { - identSensors = !identSensors; + ident_sensors = !ident_sensors; } else if (!strcmp(key, "actuators")) { - identActuators = !identActuators; + ident_actuators = !ident_actuators; } - } + }*/ FCGI_BeginJSON(context, STATUS_OK); FCGI_JSONPair("description", "MCTX3420 Server API (2013)"); FCGI_JSONPair("build_date", __DATE__ " " __TIME__); FCGI_JSONLong("api_version", API_VERSION); - if (identSensors) { + + //Time and running statistics + gettimeofday(&now, NULL); + FCGI_JSONDouble("start_time", TIMEVAL_TO_DOUBLE(g_options.start_time)); + FCGI_JSONDouble("current_time", TIMEVAL_TO_DOUBLE(now)); + FCGI_JSONDouble("running_time", TIMEVAL_DIFF(now, g_options.start_time)); + + //Sensor and actuator information + if (ident_sensors) { FCGI_JSONKey("sensors"); FCGI_JSONValue("{\n\t\t"); for (i = 0; i < NUMSENSORS; i++) { @@ -64,7 +80,7 @@ static void IdentifyHandler(FCGIContext *context, char *params) { } FCGI_JSONValue("\n\t}"); } - if (identActuators) { + if (ident_actuators) { FCGI_JSONKey("actuators"); FCGI_JSONValue("{\n\t\t"); for (i = 0; i < NUMACTUATORS; i++) { @@ -189,6 +205,87 @@ char *FCGI_KeyPair(char *in, const char **key, const char **value) return ptr; } +/** + * Aids in parsing request parameters. Expected keys along with their type + * and whether or not they're required are provided. This function will then + * parse the parameter string to find these keys. + * @param context The context to work in + * @param params The parameter string to be parsed + * @param values An array of FCGIValue's that specify expected keys + * @param count The number of elements in 'values'. + * @return true If the parameter string was parsed successfully, false otherwise. + * Modes of failure include: Invalid a parsing error on the value, + * an unknown key is specified, + * a key/value pair is specified more than once, or + * not all required keys were present. + * If this function returns false, it is guaranteed that FCGI_RejectJSON + * has already been called with the appropriate description message. + */ +bool FCGI_ParseRequest(FCGIContext *context, char *params, FCGIValue values[], size_t count) +{ + const char *key, *value; + char buf[BUFSIZ], *ptr; + size_t i; + + while ((params = FCGI_KeyPair(params, &key, &value))) { + for (i = 0; i < count; i++) { + if (!strcmp(key, values[i].key)) { + FCGIValue *val = &values[i]; + + if (FCGI_RECEIVED(val->flags)) { + snprintf(buf, BUFSIZ, "Value already specified for '%s'.", key); + FCGI_RejectJSON(context, buf); + return false; + } + val->flags |= FCGI_PARAM_RECEIVED; + + switch(FCGI_TYPE(val->flags)) { + case FCGI_BOOL_T: + *((bool*) val->value) = true; + break; + case FCGI_LONG_T: + *((long*) val->value) = strtol(value, &ptr, 10); + if (!*value || *ptr) { + snprintf(buf, BUFSIZ, "Expected int for '%s' but got '%s'", key, value); + FCGI_RejectJSON(context, FCGI_EscapeJSON(buf)); + return false; + } + break; + case FCGI_DOUBLE_T: + *((double*) val->value) = strtod(value, &ptr); + if (!*value || *ptr) { + snprintf(buf, BUFSIZ, "Expected float for '%s' but got '%s'", key, value); + FCGI_RejectJSON(context, FCGI_EscapeJSON(buf)); + return false; + } + break; + case FCGI_STRING_T: + *((const char**) val->value) = value; + break; + default: + Fatal("Invalid type %d given", FCGI_TYPE(val->flags)); + } + break; //No need to search any more + } + } //End for loop + if (i == count) { + snprintf(buf, BUFSIZ, "Unknown key '%s' specified", key); + FCGI_RejectJSON(context, FCGI_EscapeJSON(buf)); + return false; + } + } + + //Check that required parameters are received + for (i = 0; i < count; i++) { + if (FCGI_IS_REQUIRED(values[i].flags) && !FCGI_RECEIVED(values[i].flags)) { + snprintf(buf, BUFSIZ, "Key '%s' required, but was not given.", values[i].key); + FCGI_RejectJSON(context, buf); + return false; + } + } + return true; +} + /** * Begins a response to the client in JSON format. * @param context The context to work in. @@ -200,20 +297,11 @@ void FCGI_BeginJSON(FCGIContext *context, StatusCodes status_code) printf("{\r\n"); printf("\t\"module\" : \"%s\"", context->current_module); FCGI_JSONLong("status", status_code); - - // Jeremy: Should we include a timestamp in the JSON; something like this? - double start_time = g_options.start_time.tv_sec + 1e-6*(g_options.start_time.tv_usec); - struct timeval now; - gettimeofday(&now, NULL); - double current_time = now.tv_sec + 1e-6*(now.tv_usec); - FCGI_JSONDouble("start_time", start_time); - FCGI_JSONDouble("current_time", current_time); - FCGI_JSONDouble("running_time", current_time - start_time); } /** * Adds a key/value pair to a JSON response. The response must have already - * been initiated by FCGI_BeginJSON. Note that characters are not escaped. + * been initiated by FCGI_BeginJSON. Special characters are not escaped. * @param key The key of the JSON entry * @param value The value associated with the key. */ @@ -270,6 +358,36 @@ void FCGI_EndJSON() printf("\r\n}\r\n"); } +/** + * Escapes a string so it can be used as a JSON string value. + * Does not support unicode specifiers in the form of \uXXXX. + * @param buf The string to be escaped + * @return The escaped string (return value == buf) + */ +char *FCGI_EscapeJSON(char *buf) +{ + int length, i; + length = strlen(buf); + + //Escape special characters. Must count down to escape properly + for (i = length - 1; i >= 0; i--) { + if (buf[i] < 0x20) { //Control characters + buf[i] = ' '; + } else if (buf[i] == '"') { + if (i-1 >= 0 && buf[i-1] == '\\') + i--; + else + buf[i] = '\''; + } else if (buf[i] == '\\') { + if (i-1 >= 0 && buf[i-1] == '\'') + i--; + else + buf[i] = ' '; + } + } + return buf; +} + /** * To be used when the input parameters are rejected. The return data * will also have debugging information provided. @@ -355,7 +473,7 @@ void * FCGI_RequestLoop (void *data) } else if (!strcmp("control", module)) { module_handler = Control_Handler; } else if (!strcmp("sensors", module)) { - module_handler = Sensor_Handler2; + module_handler = Sensor_Handler; } context.current_module = module; diff --git a/server/fastcgi.h b/server/fastcgi.h index 9a37a6f..965cf5c 100644 --- a/server/fastcgi.h +++ b/server/fastcgi.h @@ -20,6 +20,23 @@ typedef enum StatusCodes { STATUS_OUTOFRANGE = -3 } StatusCodes; +#define FCGI_PARAM_REQUIRED (1 << 0) +#define FCGI_PARAM_RECEIVED (1 << 1) +#define FCGI_BOOL_T (1 << 2) +#define FCGI_LONG_T (1 << 3) +#define FCGI_DOUBLE_T (1 << 4) +#define FCGI_STRING_T (1 << 5) +#define FCGI_REQUIRED(x) ((x) | FCGI_PARAM_REQUIRED) +#define FCGI_IS_REQUIRED(x) ((x) & FCGI_PARAM_REQUIRED) +#define FCGI_RECEIVED(x) ((x) & FCGI_PARAM_RECEIVED) +#define FCGI_TYPE(x) ((x) & ~(FCGI_PARAM_REQUIRED | FCGI_PARAM_RECEIVED)) + +typedef struct FCGIValue { + const char *key; + void *value; + unsigned flags; +} FCGIValue; + typedef struct FCGIContext FCGIContext; typedef void (*ModuleHandler) (FCGIContext *context, char *params); @@ -27,6 +44,7 @@ extern void FCGI_BeginControl(FCGIContext *context, bool force); extern void FCGI_EndControl(FCGIContext *context); extern bool FCGI_HasControl(FCGIContext *context, const char *key); extern char *FCGI_KeyPair(char *in, const char **key, const char **value); +extern bool FCGI_ParseRequest(FCGIContext *context, char *params, FCGIValue values[], size_t count); extern void FCGI_BeginJSON(FCGIContext *context, StatusCodes status_code); extern void FCGI_JSONPair(const char *key, const char *value); extern void FCGI_JSONLong(const char *key, long value); @@ -35,6 +53,7 @@ extern void FCGI_JSONBool(const char *key, bool value); extern void FCGI_JSONKey(const char *key); extern void FCGI_PrintRaw(const char *format, ...); extern void FCGI_EndJSON(); +extern char *FCGI_EscapeJSON(char *buf); extern void FCGI_RejectJSONEx(FCGIContext *context, StatusCodes status, const char *description); extern void *FCGI_RequestLoop (void *data); diff --git a/server/sensor.c b/server/sensor.c index 9055409..f2c73c5 100644 --- a/server/sensor.c +++ b/server/sensor.c @@ -35,7 +35,7 @@ DataPoint * GetData(SensorId sensor_id, DataPoint * d) struct timeval t; gettimeofday(&t, NULL); - d->time_stamp = (t.tv_sec - g_options.start_time.tv_sec) + 1e-6*(t.tv_usec - g_options.start_time.tv_usec); + d->time_stamp = TIMEVAL_DIFF(t, g_options.start_time); // Make time relative //d->time_stamp.tv_sec -= g_options.start_time.tv_sec; @@ -385,13 +385,23 @@ void Sensor_Handler(FCGIContext *context, char * params) double start_time = -1; double end_time = -1; - double current_time = (now.tv_sec - g_options.start_time.tv_sec) + 1e-6*(now.tv_usec - g_options.start_time.tv_usec); + double current_time = TIMEVAL_DIFF(now, g_options.start_time) bool seek_time = false; bool points_specified = false; int query_size = SENSOR_QUERYBUFSIZ; int start_index = -1; int end_index = -1; + /* //Possible use case? + FCGIValue values[5] = { + {"id", &id, FCGI_REQUIRED(FCGI_INT_T)}, + {"format", &format, FCGI_STRING_T}, + {"points", &points, FCGI_STRING_T}, + {"start_time", &start_time, FCGI_DOUBLE_T}, + {"end_time", &end_time, FCGI_DOUBLE_T} + }; + if (!FCGI_ParseRequest(context, params, values, 5)) + return;*/ while ((params = FCGI_KeyPair(params, &key, &value)) != NULL) {