X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=src%2Fcommands_parser.c;h=fa4c2360101513e4796490c9720ff9b63533915f;hb=856e1f977299f26cdfb91ee2ef215455b1fba7a9;hp=62dba8617db6aeec6b5d9ac45843e326afa2506a;hpb=4fe974408da75a3aa45fcd5eabaadaa034845c1b;p=i3%2Fi3 diff --git a/src/commands_parser.c b/src/commands_parser.c index 62dba861..fa4c2360 100644 --- a/src/commands_parser.c +++ b/src/commands_parser.c @@ -1,3 +1,5 @@ +#undef I3__FILE__ +#define I3__FILE__ "commands_parser.c" /* * vim:ts=4:sw=4:expandtab * @@ -11,7 +13,7 @@ * We use a hand-written parser instead of lex/yacc because our commands are * easy for humans, not for computers. Thus, it’s quite hard to specify a * context-free grammar for the commands. A PEG grammar would be easier, but - * there’s downsides to every PEG parser generator I have come accross so far. + * there’s downsides to every PEG parser generator I have come across so far. * * This parser is basically a state machine which looks for literals or strings * and can push either on a stack. After identifying a literal or string, it @@ -32,6 +34,10 @@ #include "all.h" +// Macros to make the YAJL API a bit easier to use. +#define y(x, ...) (command_output.json_gen != NULL ? yajl_gen_##x(command_output.json_gen, ##__VA_ARGS__) : 0) +#define ystr(str) (command_output.json_gen != NULL ? yajl_gen_string(command_output.json_gen, (unsigned char *)str, strlen(str)) : 0) + /******************************************************************************* * The data structures used for parsing. Essentially the current state and a * list of tokens for that state. @@ -40,7 +46,7 @@ * input parser-specs/commands.spec. ******************************************************************************/ -#include "GENERATED_enums.h" +#include "GENERATED_command_enums.h" typedef struct token { char *name; @@ -57,7 +63,7 @@ typedef struct tokenptr { int n; } cmdp_token_ptr; -#include "GENERATED_tokens.h" +#include "GENERATED_command_tokens.h" /******************************************************************************* * The (small) stack where identified literals are stored during the parsing @@ -91,14 +97,15 @@ static void push_string(const char *identifier, char *str) { /* When we arrive here, the stack is full. This should not happen and * means there’s either a bug in this parser or the specification * contains a command with more than 10 identified tokens. */ - printf("argh! stack full\n"); + fprintf(stderr, "BUG: commands_parser stack full. This means either a bug " + "in the code, or a new command which contains more than " + "10 identified tokens.\n"); exit(1); } // XXX: ideally, this would be const char. need to check if that works with all // called functions. static char *get_string(const char *identifier) { - DLOG("Getting string %s from stack...\n", identifier); for (int c = 0; c < 10; c++) { if (stack[c].identifier == NULL) break; @@ -108,8 +115,7 @@ static char *get_string(const char *identifier) { return NULL; } -static void clear_stack() { - DLOG("clearing stack.\n"); +static void clear_stack(void) { for (int c = 0; c < 10; c++) { if (stack[c].str != NULL) free(stack[c].str); @@ -173,16 +179,21 @@ static cmdp_state state; #ifndef TEST_PARSER static Match current_match; #endif -static char *json_output; - -#include "GENERATED_call.h" +static struct CommandResultIR subcommand_output; +static struct CommandResultIR command_output; +#include "GENERATED_command_call.h" static void next_state(const cmdp_token *token) { if (token->next_state == __CALL) { - DLOG("should call stuff, yay. call_id = %d\n", - token->extra.call_identifier); - json_output = GENERATED_call(token->extra.call_identifier); + subcommand_output.json_gen = command_output.json_gen; + subcommand_output.needs_tree_render = false; + GENERATED_call(token->extra.call_identifier, &subcommand_output); + state = subcommand_output.next_state; + /* If any subcommand requires a tree_render(), we need to make the + * whole parser result request a tree_render(). */ + if (subcommand_output.needs_tree_render) + command_output.needs_tree_render = true; clear_stack(); return; } @@ -193,11 +204,79 @@ static void next_state(const cmdp_token *token) { } } -/* TODO: Return parsing errors via JSON. */ -char *parse_command(const char *input) { - DLOG("new parser handling: %s\n", input); +/* + * Parses a string (or word, if as_word is true). Extracted out of + * parse_command so that it can be used in src/workspace.c for interpreting + * workspace commands. + * + */ +char *parse_string(const char **walk, bool as_word) { + const char *beginning = *walk; + /* Handle quoted strings (or words). */ + if (**walk == '"') { + beginning++; + (*walk)++; + for (; **walk != '\0' && **walk != '"'; (*walk)++) + if (**walk == '\\' && *(*walk + 1) != '\0') + (*walk)++; + } else { + if (!as_word) { + /* For a string (starting with 's'), the delimiters are + * comma (,) and semicolon (;) which introduce a new + * operation or command, respectively. Also, newlines + * end a command. */ + while (**walk != ';' && **walk != ',' && + **walk != '\0' && **walk != '\r' && + **walk != '\n') + (*walk)++; + } else { + /* For a word, the delimiters are white space (' ' or + * '\t'), closing square bracket (]), comma (,) and + * semicolon (;). */ + while (**walk != ' ' && **walk != '\t' && + **walk != ']' && **walk != ',' && + **walk != ';' && **walk != '\r' && + **walk != '\n' && **walk != '\0') + (*walk)++; + } + } + if (*walk == beginning) + return NULL; + + char *str = scalloc(*walk - beginning + 1); + /* We copy manually to handle escaping of characters. */ + int inpos, outpos; + for (inpos = 0, outpos = 0; + inpos < (*walk - beginning); + inpos++, outpos++) { + /* We only handle escaped double quotes and backslashes to not break + * backwards compatibility with people using \w in regular expressions + * etc. */ + if (beginning[inpos] == '\\' && (beginning[inpos + 1] == '"' || beginning[inpos + 1] == '\\')) + inpos++; + str[outpos] = beginning[inpos]; + } + + return str; +} + +/* + * Parses and executes the given command. If a caller-allocated yajl_gen is + * passed, a json reply will be generated in the format specified by the ipc + * protocol. Pass NULL if no json reply is required. + * + * Free the returned CommandResult with command_result_free(). + */ +CommandResult *parse_command(const char *input, yajl_gen gen) { + DLOG("COMMAND: *%s*\n", input); state = INITIAL; - json_output = NULL; + CommandResult *result = scalloc(sizeof(CommandResult)); + + /* A YAJL JSON generator used for formatting replies. */ + command_output.json_gen = gen; + + y(array_open); + command_output.needs_tree_render = false; const char *walk = input; const size_t len = strlen(input); @@ -205,32 +284,28 @@ char *parse_command(const char *input) { const cmdp_token *token; bool token_handled; - // TODO: make this testable +// TODO: make this testable #ifndef TEST_PARSER - cmd_criteria_init(¤t_match); + cmd_criteria_init(¤t_match, &subcommand_output); #endif /* The "<=" operator is intentional: We also handle the terminating 0-byte * explicitly by looking for an 'end' token. */ - while ((walk - input) <= len) { + while ((size_t)(walk - input) <= len) { /* skip whitespace and newlines before every token */ while ((*walk == ' ' || *walk == '\t' || - *walk == '\r' || *walk == '\n') && *walk != '\0') + *walk == '\r' || *walk == '\n') && + *walk != '\0') walk++; - DLOG("remaining input = %s\n", walk); - cmdp_token_ptr *ptr = &(tokens[state]); token_handled = false; for (c = 0; c < ptr->n; c++) { token = &(ptr->array[c]); - DLOG("trying token %d = %s\n", c, token->name); /* A literal. */ if (token->name[0] == '\'') { - DLOG("literal\n"); if (strncasecmp(walk, token->name + 1, strlen(token->name) - 1) == 0) { - DLOG("found literal, moving to next state\n"); if (token->identifier != NULL) push_string(token->identifier, sstrdup(token->name + 1)); walk += strlen(token->name) - 1; @@ -243,41 +318,10 @@ char *parse_command(const char *input) { if (strcmp(token->name, "string") == 0 || strcmp(token->name, "word") == 0) { - DLOG("parsing this as a string\n"); - const char *beginning = walk; - /* Handle quoted strings (or words). */ - if (*walk == '"') { - beginning++; - walk++; - while (*walk != '"' || *(walk-1) == '\\') - walk++; - } else { - if (token->name[0] == 's') { - /* For a string (starting with 's'), the delimiters are - * comma (,) and semicolon (;) which introduce a new - * operation or command, respectively. Also, newlines - * end a command. */ - while (*walk != ';' && *walk != ',' && - *walk != '\0' && *walk != '\r' && - *walk != '\n') - walk++; - } else { - /* For a word, the delimiters are white space (' ' or - * '\t'), closing square bracket (]), comma (,) and - * semicolon (;). */ - while (*walk != ' ' && *walk != '\t' && - *walk != ']' && *walk != ',' && - *walk != ';' && *walk != '\r' && - *walk != '\n' && *walk != '\0') - walk++; - } - } - if (walk != beginning) { - char *str = scalloc(walk-beginning + 1); - strncpy(str, beginning, walk-beginning); + char *str = parse_string(&walk, (token->name[0] != 's')); + if (str != NULL) { if (token->identifier) push_string(token->identifier, str); - DLOG("str is \"%s\"\n", str); /* If we are at the end of a quoted string, skip the ending * double quote. */ if (*walk == '"') @@ -289,24 +333,22 @@ char *parse_command(const char *input) { } if (strcmp(token->name, "end") == 0) { - DLOG("checking for the end token.\n"); if (*walk == '\0' || *walk == ',' || *walk == ';') { - DLOG("yes, indeed. end\n"); next_state(token); token_handled = true; - /* To make sure we start with an appropriate matching +/* To make sure we start with an appropriate matching * datastructure for commands which do *not* specify any * criteria, we re-initialize the criteria system after * every command. */ - // TODO: make this testable +// TODO: make this testable #ifndef TEST_PARSER if (*walk == '\0' || *walk == ';') - cmd_criteria_init(¤t_match); + cmd_criteria_init(¤t_match, &subcommand_output); #endif walk++; break; - } - } + } + } } if (!token_handled) { @@ -356,18 +398,51 @@ char *parse_command(const char *input) { position[(copywalk - input)] = (copywalk >= walk ? '^' : ' '); position[len] = '\0'; - printf("%s\n", errormessage); - printf("Your command: %s\n", input); - printf(" %s\n", position); + ELOG("%s\n", errormessage); + ELOG("Your command: %s\n", input); + ELOG(" %s\n", position); + + result->parse_error = true; + result->error_message = errormessage; + + /* Format this error message as a JSON reply. */ + y(map_open); + ystr("success"); + y(bool, false); + /* We set parse_error to true to distinguish this from other + * errors. i3-nagbar is spawned upon keypresses only for parser + * errors. */ + ystr("parse_error"); + y(bool, true); + ystr("error"); + ystr(errormessage); + ystr("input"); + ystr(input); + ystr("errorposition"); + ystr(position); + y(map_close); free(position); - free(errormessage); + clear_stack(); break; } } - DLOG("json_output = %s\n", json_output); - return json_output; + y(array_close); + + result->needs_tree_render = command_output.needs_tree_render; + return result; +} + +/* + * Frees a CommandResult + */ +void command_result_free(CommandResult *result) { + if (result == NULL) + return; + + FREE(result->error_message); + FREE(result); } /******************************************************************************* @@ -379,15 +454,23 @@ char *parse_command(const char *input) { /* * Logs the given message to stdout while prefixing the current time to it, - * but only if the corresponding debug loglevel was activated. + * but only if debug logging was activated. * This is to be called by DLOG() which includes filename/linenumber * */ -void debuglog(uint64_t lev, char *fmt, ...) { +void debuglog(char *fmt, ...) { + va_list args; + + va_start(args, fmt); + fprintf(stdout, "# "); + vfprintf(stdout, fmt, args); + va_end(args); +} + +void errorlog(char *fmt, ...) { va_list args; va_start(args, fmt); - fprintf(stderr, "# "); vfprintf(stderr, fmt, args); va_end(args); } @@ -397,6 +480,12 @@ int main(int argc, char *argv[]) { fprintf(stderr, "Syntax: %s \n", argv[0]); return 1; } - parse_command(argv[1]); + yajl_gen gen = yajl_gen_alloc(NULL); + + CommandResult *result = parse_command(argv[1], gen); + + command_result_free(result); + + yajl_gen_free(gen); } #endif