fxsdk/fxlink/filter.c

195 lines
4.7 KiB
C
Raw Normal View History

#include "filter.h"
#include "util.h"
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
//---
// Property parser
//---
/* skip_spaces(): Skip spaces, returns true if end of string is reached */
bool skip_spaces(char const **input)
{
while(isspace(**input)) (*input)++;
return (**input == 0);
}
/* isword(): Identify valid word characters for the filter */
bool isword(int c)
{
return c && !strchr(" \t\n,;=", c);
}
/* read_word(): Copy the next word in the string, assumes word is non-empty */
char *read_word(char const **input)
{
char const *str = *input;
while(**input && isword(**input)) (*input)++;
return strndup(str, *input - str);
}
enum {
T_END, /* End of string */
T_PROP, /* Property; (*name) and (*value) are set */
T_COMMA = ',', /* Comma character (property separator) */
T_SEMI = ';', /* Semicolon character (option separator) */
};
/* lex(): Read a token from the input source
Returns the token type, updates (*input) and sets (*name) and (*value) to
either NULL or some freshly-allocated copies of the name and (optional)
value of the property (always NULL unless T_PROP is returned). The caller
should free() both. */
static int lex(char const **input, char **name, char **value)
{
*name = *value = NULL;
if(skip_spaces(input)) return T_END;
if(**input == ',' || **input == ';') {
(*input)++;
return (*input)[-1];
}
if(!isword(**input)) {
wrn("expected property name in filter, skipping '%c'", **input);
(*input)++;
return lex(input, name, value);
}
*name = read_word(input);
if(skip_spaces(input) || **input != '=')
return T_PROP;
(*input)++;
if(skip_spaces(input))
wrn("no value after '=' in filter property '%s'", *name);
else if(!isword(**input))
wrn("ignoring invalid value for filter property '%s'", *name);
else
*value = read_word(input);
return T_PROP;
}
filter_t *filter_parse(char const *input)
{
char *name=NULL, *value=NULL;
int t;
/* Create an initial filter with a single otion */
filter_t *filter = malloc(sizeof *filter);
if(!filter) return NULL;
filter->options = calloc(1, sizeof(properties_t));
if(!filter->options) {
free(filter);
return NULL;
}
filter->length = 1;
/* Current option */
properties_t *option = &filter->options[0];
while((t = lex(&input, &name, &value)) != T_END) {
/* Ignore property separators (tokens are already separated) */
if(t == ',') continue;
/* Add a new option in the filter */
if(t == ';') {
size_t new_size = (filter->length + 1) * sizeof(properties_t);
properties_t *new_options = realloc(filter->options, new_size);
if(!new_options) continue;
filter->options = new_options;
option = &filter->options[filter->length++];
*option = (properties_t){ 0 };
continue;
}
/* Add a new property to the current option */
if(!strcmp(name, "p7") && !value)
option->p7 = true;
else if(!strcmp(name, "mass_storage") && !value)
option->mass_storage = true;
else if(!strcmp(name, "series_cg") && !value)
option->series_cg = true;
else if(!strcmp(name, "series_g3") && !value)
option->series_g3 = true;
else if(!strcmp(name, "serial_number") && value) {
option->serial_number = strdup(value);
}
else wrn("ignoring invalid filter property: '%s' %s value", name,
value ? "with" : "without");
free(name);
free(value);
}
return filter;
}
void filter_free(filter_t *filter)
{
if(!filter) return;
for(size_t i = 0; i < filter->length; i++)
free(filter->options[i].serial_number);
free(filter->options);
free(filter);
}
//---
// Filtering API
//---
void filter_clean_libusb(filter_t *filter)
{
if(!filter) return;
for(size_t i = 0; i < filter->length; i++) {
properties_t *prop = &filter->options[i];
/* Suppress series_cg and series_g3, which are based off the USB Mass
Storage metadata provided only by UDisks2 */
if(prop->series_cg) {
wrn("ignoring series_cg in libusb filter (cannot be detected)");
prop->series_cg = false;
}
if(prop->series_g3) {
wrn("ignoring series_g3 in libusb filter (cannot be detected)");
prop->series_g3 = false;
}
}
}
void filter_clean_udisks2(filter_t *filter)
{
/* Every property can be used */
(void)filter;
}
bool filter_match(properties_t const *props, filter_t const *filter)
{
/* No filter is a pass-through */
if(!filter || !filter->length)
return true;
for(size_t i = 0; i < filter->length; i++) {
if(properties_match(props, &filter->options[i]))
return true;
}
return false;
}
void filter_print(FILE *fp, filter_t const *filter)
{
#define output(...) { \
if(sep) fprintf(fp, ", "); \
fprintf(fp, __VA_ARGS__); \
sep = true; \
}
for(size_t i = 0; i < filter->length; i++) {
if(i > 0) printf("; ");
properties_t *prop = &filter->options[i];
properties_print(fp, prop);
}
}