/* * wee-eval.c - evaluate expressions with references to internal vars * * Copyright (C) 2012-2020 Sébastien Helleu * * This file is part of WeeChat, the extensible chat client. * * WeeChat is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * WeeChat is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with WeeChat. If not, see . */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #include #include "weechat.h" #include "wee-eval.h" #include "wee-calc.h" #include "wee-config-file.h" #include "wee-hashtable.h" #include "wee-hdata.h" #include "wee-hook.h" #include "wee-secure.h" #include "wee-string.h" #include "wee-utf8.h" #include "../gui/gui-buffer.h" #include "../gui/gui-chat.h" #include "../gui/gui-color.h" #include "../gui/gui-window.h" #include "../plugins/plugin.h" #define EVAL_DEBUG(msg, argz...) \ if (eval_context->debug) \ eval_debug_message (eval_context, msg, ##argz); char *logical_ops[EVAL_NUM_LOGICAL_OPS] = { "||", "&&" }; char *comparisons[EVAL_NUM_COMPARISONS] = { "=~", "!~", "=*", "!*", "==", "!=", "<=", "<", ">=", ">" }; char *eval_replace_vars (const char *expr, struct t_eval_context *eval_context); char *eval_expression_condition (const char *expr, struct t_eval_context *eval_context); /* * Adds a debug message in the debug output. */ void eval_debug_message (struct t_eval_context *eval_context, char *message, ...) { weechat_va_format (message); if (!vbuffer) return; if (*(eval_context->debug)[0]) string_dyn_concat (eval_context->debug, "\n"); string_dyn_concat (eval_context->debug, vbuffer); free (vbuffer); } /* * Checks if a value is true: a value is true if string is non-NULL, non-empty * and different from "0". * * Returns: * 1: value is true * 0: value is false */ int eval_is_true (const char *value) { return (value && value[0] && (strcmp (value, "0") != 0)) ? 1 : 0; } /* * Searches a string in another at same level (skip sub-expressions between * prefix/suffix). * * If escape is 1, the prefix can be escaped with '\' (and then is ignored). * * For example: * eval_strstr_level ("(x || y) || z", "||", eval_context, "(", ")", 0) * will return a pointer on "|| z" (because the first "||" is * in a sub-expression, which is skipped). * * Returns pointer to string found, or NULL if not found. */ const char * eval_strstr_level (const char *string, const char *search, struct t_eval_context *eval_context, const char *extra_prefix, const char *extra_suffix, int escape) { const char *ptr_string; int level, length_search; int length_prefix, length_prefix2, length_suffix, length_suffix2; EVAL_DEBUG("eval_strstr_level(\"%s\", \"%s\", \"%s\", \"%s\", %d)", string, search, extra_prefix, extra_suffix, escape); if (!string || !search) return NULL; length_search = strlen (search); length_prefix = strlen (eval_context->prefix); length_suffix = strlen (eval_context->suffix); length_prefix2 = (extra_prefix) ? strlen (extra_prefix) : 0; length_suffix2 = (extra_suffix) ? strlen (extra_suffix) : 0; ptr_string = string; level = 0; while (ptr_string[0]) { if (escape && (ptr_string[0] == '\\') && ((ptr_string[1] == eval_context->prefix[0]) || ((length_suffix2 > 0) && ptr_string[1] == extra_prefix[0]))) { ptr_string++; } else if (strncmp (ptr_string, eval_context->prefix, length_prefix) == 0) { level++; ptr_string += length_prefix; } else if ((length_prefix2 > 0) && (strncmp (ptr_string, extra_prefix, length_prefix2) == 0)) { level++; ptr_string += length_prefix2; } else if (strncmp (ptr_string, eval_context->suffix, length_suffix) == 0) { if (level > 0) level--; ptr_string += length_suffix; } else if ((length_suffix2 > 0) && (strncmp (ptr_string, extra_suffix, length_suffix2) == 0)) { if (level > 0) level--; ptr_string += length_suffix2; } else if ((level == 0) && (strncmp (ptr_string, search, length_search) == 0)) { return ptr_string; } else { ptr_string++; } } return NULL; } /* * Gets value of hdata using "path" to a variable. * * Note: result must be freed after use. */ char * eval_hdata_get_value (struct t_hdata *hdata, void *pointer, const char *path, struct t_eval_context *eval_context) { char *value, *old_value, *var_name, str_value[128], *pos; const char *ptr_value, *hdata_name, *ptr_var_name; int type; struct t_hashtable *hashtable; EVAL_DEBUG("eval_hdata_get_value(\"%s\", 0x%lx, \"%s\")", hdata->name, pointer, path); value = NULL; var_name = NULL; /* NULL pointer? return empty string */ if (!pointer) return strdup (""); /* no path? just return current pointer as string */ if (!path || !path[0]) { snprintf (str_value, sizeof (str_value), "0x%lx", (unsigned long)pointer); return strdup (str_value); } /* * look for name of hdata, for example in "window.buffer.full_name", the * hdata name is "window" */ pos = strchr (path, '.'); if (pos > path) var_name = string_strndup (path, pos - path); else var_name = strdup (path); if (!var_name) goto end; /* search type of variable in hdata */ hdata_get_index_and_name (var_name, NULL, &ptr_var_name); type = hdata_get_var_type (hdata, ptr_var_name); if (type < 0) goto end; /* build a string with the value or variable */ switch (type) { case WEECHAT_HDATA_CHAR: snprintf (str_value, sizeof (str_value), "%c", hdata_char (hdata, pointer, var_name)); value = strdup (str_value); break; case WEECHAT_HDATA_INTEGER: snprintf (str_value, sizeof (str_value), "%d", hdata_integer (hdata, pointer, var_name)); value = strdup (str_value); break; case WEECHAT_HDATA_LONG: snprintf (str_value, sizeof (str_value), "%ld", hdata_long (hdata, pointer, var_name)); value = strdup (str_value); break; case WEECHAT_HDATA_STRING: case WEECHAT_HDATA_SHARED_STRING: ptr_value = hdata_string (hdata, pointer, var_name); value = (ptr_value) ? strdup (ptr_value) : NULL; break; case WEECHAT_HDATA_POINTER: pointer = hdata_pointer (hdata, pointer, var_name); snprintf (str_value, sizeof (str_value), "0x%lx", (unsigned long)pointer); value = strdup (str_value); break; case WEECHAT_HDATA_TIME: snprintf (str_value, sizeof (str_value), "%lld", (long long)hdata_time (hdata, pointer, var_name)); value = strdup (str_value); break; case WEECHAT_HDATA_HASHTABLE: pointer = hdata_hashtable (hdata, pointer, var_name); if (pos) { /* * for a hashtable, if there is a "." after name of hdata, * get the value for this key in hashtable */ hashtable = pointer; ptr_value = hashtable_get (hashtable, pos + 1); if (ptr_value) { switch (hashtable->type_values) { case HASHTABLE_INTEGER: snprintf (str_value, sizeof (str_value), "%d", *((int *)ptr_value)); value = strdup (str_value); break; case HASHTABLE_STRING: value = strdup (ptr_value); break; case HASHTABLE_POINTER: case HASHTABLE_BUFFER: snprintf (str_value, sizeof (str_value), "0x%lx", (unsigned long)ptr_value); value = strdup (str_value); break; case HASHTABLE_TIME: snprintf (str_value, sizeof (str_value), "%lld", (long long)(*((time_t *)ptr_value))); value = strdup (str_value); break; case HASHTABLE_NUM_TYPES: break; } } } else { snprintf (str_value, sizeof (str_value), "0x%lx", (unsigned long)pointer); value = strdup (str_value); } break; } /* * if we are on a pointer and that something else is in path (after "."), * go on with this pointer and remaining path */ if ((type == WEECHAT_HDATA_POINTER) && pos) { hdata_name = hdata_get_var_hdata (hdata, var_name); if (!hdata_name) goto end; hdata = hook_hdata_get (NULL, hdata_name); old_value = value; value = eval_hdata_get_value (hdata, pointer, (pos) ? pos + 1 : NULL, eval_context); if (old_value) free (old_value); } end: if (var_name) free (var_name); return value; } /* * Replaces variables, which can be, by order of priority: * 1. an extra variable from hashtable "extra_vars" * 2. a string to evaluate (format: eval:xxx) * 3. a string with escaped chars (format: esc:xxx or \xxx) * 4. a string with chars to hide (format: hide:char,string) * 5. a string with max chars (format: cut:max,suffix,string or * cut:+max,suffix,string) or max chars on screen * (format: cutscr:max,suffix,string or cutscr:+max,suffix,string) * 6. a reversed string (format: rev:xxx) or reversed string for screen, * color codes are not reversed (format: revscr:xxx) * 7. a repeated string (format: repeat:count,string) * 8. length of a string (format: length:xxx) or length of a string on screen * (format: lengthscr:xxx); color codes are ignored * 9. a regex group captured (format: re:N (0.99) or re:+) * 10. a color (format: color:xxx) * 11. a modifier (format: modifier:name,data,xxx) * 12. an info (format: info:name,arguments) * 13. current date/time (format: date or date:xxx) * 14. an environment variable (format: env:XXX) * 15. a ternary operator (format: if:condition?value_if_true:value_if_false) * 16. calculate result of an expression (format: calc:xxx) * 17. an option (format: file.section.option) * 18. a buffer local variable * 19. a hdata variable (format: hdata.var1.var2 or hdata[list].var1.var2 * or hdata[ptr].var1.var2) * * See /help in WeeChat for examples. * * Note: result must be freed after use. */ char * eval_replace_vars_cb (void *data, const char *text) { struct t_eval_context *eval_context; struct t_config_option *ptr_option; struct t_gui_buffer *ptr_buffer; char str_value[512], *value, *pos, *pos1, *pos2, *hdata_name, *list_name; char *tmp, *tmp2, *info_name, *hide_char, *hidden_string, *error; char *condition, *modifier_name, *modifier_data; const char *ptr_value, *ptr_arguments, *ptr_string; struct t_hdata *hdata; void *pointer; int i, length_hide_char, length, index, rc, screen; int count_suffix; long number; unsigned long ptr; time_t date; struct tm *date_tmp; eval_context = (struct t_eval_context *)data; EVAL_DEBUG("eval_replace_vars_cb(\"%s\")", text); /* 1. variable in hashtable "extra_vars" */ if (eval_context->extra_vars) { ptr_value = hashtable_get (eval_context->extra_vars, text); if (ptr_value) { if (eval_context->extra_vars_eval) { tmp = strdup (ptr_value); if (!tmp) return NULL; hashtable_remove (eval_context->extra_vars, text); value = eval_replace_vars (tmp, eval_context); hashtable_set (eval_context->extra_vars, text, tmp); free (tmp); return value; } else { return strdup (ptr_value); } } } /* * 2. force evaluation of string (recursive call) * --> use with caution: the text must be safe! */ if (strncmp (text, "eval:", 5) == 0) { return eval_replace_vars (text + 5, eval_context); } /* 3. convert escaped chars */ if (strncmp (text, "esc:", 4) == 0) return string_convert_escaped_chars (text + 4); if ((text[0] == '\\') && text[1] && (text[1] != '\\')) return string_convert_escaped_chars (text); /* 4. hide chars: replace all chars by a given char/string */ if (strncmp (text, "hide:", 5) == 0) { hidden_string = NULL; ptr_string = strchr (text + 5, (text[5] == ',') ? ';' : ','); if (!ptr_string) return strdup (""); hide_char = string_strndup (text + 5, ptr_string - text - 5); if (hide_char) { length_hide_char = strlen (hide_char); length = utf8_strlen (ptr_string + 1); hidden_string = malloc ((length * length_hide_char) + 1); if (hidden_string) { index = 0; for (i = 0; i < length; i++) { memcpy (hidden_string + index, hide_char, length_hide_char); index += length_hide_char; } hidden_string[length * length_hide_char] = '\0'; } free (hide_char); } return (hidden_string) ? hidden_string : strdup (""); } /* * 5. cut chars: * cut: max number of chars, and add an optional suffix when the * string is cut * cutscr: max number of chars displayed on screen, and add an optional * suffix when the string is cut */ if ((strncmp (text, "cut:", 4) == 0) || (strncmp (text, "cutscr:", 7) == 0)) { if (strncmp (text, "cut:", 4) == 0) { screen = 0; length = 4; } else { screen = 1; length = 7; } pos = strchr (text + length, ','); if (!pos) return strdup (""); count_suffix = 0; if (text[length] == '+') { length++; count_suffix = 1; } pos2 = strchr (pos + 1, ','); if (!pos2) return strdup (""); tmp = strndup (text + length, pos - text - length); if (!tmp) return strdup (""); number = strtol (tmp, &error, 10); if (!error || error[0] || (number < 0)) { free (tmp); return strdup (""); } free (tmp); tmp = strndup (pos + 1, pos2 - pos - 1); if (!tmp) return strdup (""); value = string_cut (pos2 + 1, number, count_suffix, screen, tmp); free (tmp); return value; } /* 6. reverse string */ if (strncmp (text, "rev:", 4) == 0) return string_reverse (text + 4); if (strncmp (text, "revscr:", 7) == 0) return string_reverse_screen (text + 7); /* 7. repeated string */ if (strncmp (text, "repeat:", 7) == 0) { pos = strchr (text + 7, ','); if (!pos) return strdup (""); tmp = strndup (text + 7, pos - text - 7); if (!tmp) return strdup (""); number = strtol (tmp, &error, 10); if (!error || error[0] || (number < 0)) { free (tmp); return strdup (""); } free (tmp); return string_repeat (pos + 1, number); } /* * 8. length of string: * length: number of chars * lengthscr: number of chars displayed on screen */ if (strncmp (text, "length:", 7) == 0) { length = gui_chat_strlen (text + 7); snprintf (str_value, sizeof (str_value), "%d", length); return strdup (str_value); } if (strncmp (text, "lengthscr:", 10) == 0) { length = gui_chat_strlen_screen (text + 10); snprintf (str_value, sizeof (str_value), "%d", length); return strdup (str_value); } /* 9. regex group captured */ if (strncmp (text, "re:", 3) == 0) { if (eval_context->regex && eval_context->regex->result) { if (strcmp (text + 3, "+") == 0) number = eval_context->regex->last_match; else if (strcmp (text + 3, "#") == 0) { snprintf (str_value, sizeof (str_value), "%d", eval_context->regex->last_match); return strdup (str_value); } else { number = strtol (text + 3, &error, 10); if (!error || error[0]) number = -1; } if ((number >= 0) && (number <= eval_context->regex->last_match)) { return string_strndup ( eval_context->regex->result + eval_context->regex->match[number].rm_so, eval_context->regex->match[number].rm_eo - eval_context->regex->match[number].rm_so); } } return strdup (""); } /* 10. color code */ if (strncmp (text, "color:", 6) == 0) { ptr_value = gui_color_search_config (text + 6); if (ptr_value) return strdup (ptr_value); ptr_value = gui_color_get_custom (text + 6); return strdup ((ptr_value) ? ptr_value : ""); } /* 11. modifier */ if (strncmp (text, "modifier:", 9) == 0) { value = NULL; ptr_arguments = strchr (text + 9, ','); if (!ptr_arguments) return strdup (""); ptr_arguments++; ptr_string = strchr (ptr_arguments, ','); if (!ptr_string) return strdup (""); ptr_string++; modifier_name = string_strndup (text + 9, ptr_arguments - 1 - text - 9); modifier_data = string_strndup (ptr_arguments, ptr_string - 1 - ptr_arguments); value = hook_modifier_exec (NULL, modifier_name, modifier_data, ptr_string); if (modifier_name) free (modifier_name); if (modifier_data) free (modifier_data); return (value) ? value : strdup (""); } /* 12. info */ if (strncmp (text, "info:", 5) == 0) { value = NULL; ptr_arguments = strchr (text + 5, ','); if (ptr_arguments) { info_name = string_strndup (text + 5, ptr_arguments - text - 5); ptr_arguments++; } else info_name = strdup (text + 5); if (info_name) { value = hook_info_get (NULL, info_name, ptr_arguments); free (info_name); } return (value) ? value : strdup (""); } /* 13. current date/time */ if ((strncmp (text, "date", 4) == 0) && (!text[4] || (text[4] == ':'))) { date = time (NULL); date_tmp = localtime (&date); if (!date_tmp) return strdup (""); rc = (int) strftime (str_value, sizeof (str_value), (text[4] == ':') ? text + 5 : "%F %T", date_tmp); return strdup ((rc > 0) ? str_value : ""); } /* 14. environment variable */ if (strncmp (text, "env:", 4) == 0) { ptr_value = getenv (text + 4); if (ptr_value) return strdup (ptr_value); } /* 15: ternary operator: if:condition?value_if_true:value_if_false */ if (strncmp (text, "if:", 3) == 0) { value = NULL; pos = (char *)eval_strstr_level (text + 3, "?", eval_context, NULL, NULL, 1); pos2 = (pos) ? (char *)eval_strstr_level (pos + 1, ":", eval_context, NULL, NULL, 1) : NULL; condition = (pos) ? strndup (text + 3, pos - (text + 3)) : strdup (text + 3); if (!condition) return strdup (""); tmp = eval_replace_vars (condition, eval_context); tmp2 = eval_expression_condition ((tmp) ? tmp : "", eval_context); rc = eval_is_true (tmp2); if (tmp) free (tmp); if (tmp2) free (tmp2); if (rc) { /* * condition is true: return the "value_if_true" * (or EVAL_STR_TRUE if value is missing) */ if (pos) { tmp = (pos2) ? strndup (pos + 1, pos2 - pos - 1) : strdup (pos + 1); if (tmp) { value = eval_replace_vars (tmp, eval_context); free (tmp); } } else { value = strdup (EVAL_STR_TRUE); } } else { /* * condition is false: return the "value_if_false" * (or EVAL_STR_FALSE if both values are missing) */ if (pos2) { value = eval_replace_vars (pos2 + 1, eval_context); } else { if (!pos) value = strdup (EVAL_STR_FALSE); } } free (condition); return (value) ? value : strdup (""); } /* * 16. calculate the result of an expression * (with number, operators and parentheses) */ if (strncmp (text, "calc:", 5) == 0) { return calc_expression (text + 5); } /* 17. option: if found, return this value */ if (strncmp (text, "sec.data.", 9) == 0) { ptr_value = hashtable_get (secure_hashtable_data, text + 9); return strdup ((ptr_value) ? ptr_value : ""); } else { config_file_search_with_string (text, NULL, NULL, &ptr_option, NULL); if (ptr_option) { if (!ptr_option->value) return strdup (""); switch (ptr_option->type) { case CONFIG_OPTION_TYPE_BOOLEAN: return strdup (CONFIG_BOOLEAN(ptr_option) ? EVAL_STR_TRUE : EVAL_STR_FALSE); case CONFIG_OPTION_TYPE_INTEGER: if (ptr_option->string_values) return strdup (ptr_option->string_values[CONFIG_INTEGER(ptr_option)]); snprintf (str_value, sizeof (str_value), "%d", CONFIG_INTEGER(ptr_option)); return strdup (str_value); case CONFIG_OPTION_TYPE_STRING: return strdup (CONFIG_STRING(ptr_option)); case CONFIG_OPTION_TYPE_COLOR: return strdup (gui_color_get_name (CONFIG_COLOR(ptr_option))); case CONFIG_NUM_OPTION_TYPES: return strdup (""); } } } /* 18. local variable in buffer */ ptr_buffer = hashtable_get (eval_context->pointers, "buffer"); if (ptr_buffer) { ptr_value = hashtable_get (ptr_buffer->local_variables, text); if (ptr_value) return strdup (ptr_value); } /* 19. hdata */ value = NULL; hdata_name = NULL; list_name = NULL; pointer = NULL; pos = strchr (text, '.'); if (pos > text) hdata_name = string_strndup (text, pos - text); else hdata_name = strdup (text); if (!hdata_name) goto end; pos1 = strchr (hdata_name, '['); if (pos1 > hdata_name) { pos2 = strchr (pos1 + 1, ']'); if (pos2 > pos1 + 1) { list_name = string_strndup (pos1 + 1, pos2 - pos1 - 1); } tmp = string_strndup (hdata_name, pos1 - hdata_name); if (tmp) { free (hdata_name); hdata_name = tmp; } } hdata = hook_hdata_get (NULL, hdata_name); if (!hdata) goto end; if (list_name) { if (strncmp (list_name, "0x", 2) == 0) { rc = sscanf (list_name, "%lx", &ptr); if ((rc != EOF) && (rc != 0)) { pointer = (void *)ptr; if (!hdata_check_pointer (hdata, NULL, pointer)) goto end; } else goto end; } else pointer = hdata_get_list (hdata, list_name); } if (!pointer) { pointer = hashtable_get (eval_context->pointers, hdata_name); if (!pointer) goto end; } value = eval_hdata_get_value (hdata, pointer, (pos) ? pos + 1 : NULL, eval_context); end: if (hdata_name) free (hdata_name); if (list_name) free (list_name); return (value) ? value : strdup (""); } /* * Replaces variables in a string. * * Note: result must be freed after use. */ char * eval_replace_vars (const char *expr, struct t_eval_context *eval_context) { const char *no_replace_prefix_list[] = { "if:", NULL }; char *result; EVAL_DEBUG("eval_replace_vars(\"%s\")", expr); eval_context->recursion_count++; if (eval_context->recursion_count < EVAL_RECURSION_MAX) { result = string_replace_with_callback (expr, eval_context->prefix, eval_context->suffix, no_replace_prefix_list, &eval_replace_vars_cb, eval_context, NULL); } else { result = strdup (""); } eval_context->recursion_count--; return result; } /* * Compares two expressions. * * Returns: * "1": comparison is true * "0": comparison is false * * Examples: * "15 > 2": returns "1" * "abc == def": returns "0" * * Note: result must be freed after use. */ char * eval_compare (const char *expr1, int comparison, const char *expr2, struct t_eval_context *eval_context) { int rc, string_compare, length1, length2; regex_t regex; double value1, value2; char *error; EVAL_DEBUG("eval_compare(\"%s\", \"%s\", \"%s\")", expr1, comparisons[comparison], expr2); rc = 0; string_compare = 0; if (!expr1 || !expr2) goto end; if ((comparison == EVAL_COMPARE_REGEX_MATCHING) || (comparison == EVAL_COMPARE_REGEX_NOT_MATCHING)) { if (string_regcomp (®ex, expr2, REG_EXTENDED | REG_ICASE | REG_NOSUB) != 0) { goto end; } rc = (regexec (®ex, expr1, 0, NULL, 0) == 0) ? 1 : 0; regfree (®ex); if (comparison == EVAL_COMPARE_REGEX_NOT_MATCHING) rc ^= 1; goto end; } else if ((comparison == EVAL_COMPARE_STRING_MATCHING) || (comparison == EVAL_COMPARE_STRING_NOT_MATCHING)) { rc = string_match (expr1, expr2, 0); if (comparison == EVAL_COMPARE_STRING_NOT_MATCHING) rc ^= 1; goto end; } length1 = strlen (expr1); length2 = strlen (expr2); /* * string comparison is forced if expr1 and expr2 have double quotes at * beginning/end */ if (((length1 == 0) || ((expr1[0] == '"') && expr1[length1 - 1] == '"')) && ((length2 == 0) || ((expr2[0] == '"') && expr2[length2 - 1] == '"'))) { string_compare = 1; } if (!string_compare) { value1 = strtod (expr1, &error); if (!error || error[0]) { string_compare = 1; } else { value2 = strtod (expr2, &error); if (!error || error[0]) string_compare = 1; } } if (string_compare) rc = strcmp (expr1, expr2); else rc = (value1 < value2) ? -1 : ((value1 > value2) ? 1 : 0); switch (comparison) { case EVAL_COMPARE_EQUAL: rc = (rc == 0); break; case EVAL_COMPARE_NOT_EQUAL: rc = (rc != 0); break; case EVAL_COMPARE_LESS_EQUAL: rc = (rc <= 0); break; case EVAL_COMPARE_LESS: rc = (rc < 0); break; case EVAL_COMPARE_GREATER_EQUAL: rc = (rc >= 0); break; case EVAL_COMPARE_GREATER: rc = (rc > 0); break; case EVAL_NUM_COMPARISONS: break; } end: return strdup ((rc) ? EVAL_STR_TRUE : EVAL_STR_FALSE); } /* * Evaluates a condition (this function must not be called directly). * * For return value, see function eval_expression(). * * Note: result must be freed after use (if not NULL). */ char * eval_expression_condition (const char *expr, struct t_eval_context *eval_context) { int logic, comp, length, level, rc; const char *pos, *pos_end; char *expr2, *sub_expr, *value, *tmp_value, *tmp_value2; EVAL_DEBUG("eval_expression_condition(\"%s\")", expr); value = NULL; if (!expr) return NULL; if (!expr[0]) return strdup (expr); /* skip spaces at beginning of string */ while (expr[0] == ' ') { expr++; } if (!expr[0]) return strdup (expr); /* skip spaces at end of string */ pos_end = expr + strlen (expr) - 1; while ((pos_end > expr) && (pos_end[0] == ' ')) { pos_end--; } expr2 = string_strndup (expr, pos_end + 1 - expr); if (!expr2) return NULL; /* * search for a logical operator, and if one is found: * - split expression into two sub-expressions * - evaluate first sub-expression * - if needed, evaluate second sub-expression * - return result */ for (logic = 0; logic < EVAL_NUM_LOGICAL_OPS; logic++) { pos = eval_strstr_level (expr2, logical_ops[logic], eval_context, "(", ")", 0); if (pos > expr2) { pos_end = pos - 1; while ((pos_end > expr2) && (pos_end[0] == ' ')) { pos_end--; } sub_expr = string_strndup (expr2, pos_end + 1 - expr2); if (!sub_expr) goto end; tmp_value = eval_expression_condition (sub_expr, eval_context); free (sub_expr); rc = eval_is_true (tmp_value); if (tmp_value) free (tmp_value); /* * if rc == 0 with "&&" or rc == 1 with "||", no need to * evaluate second sub-expression, just return the rc */ if ((!rc && (logic == EVAL_LOGICAL_OP_AND)) || (rc && (logic == EVAL_LOGICAL_OP_OR))) { value = strdup ((rc) ? EVAL_STR_TRUE : EVAL_STR_FALSE); goto end; } pos += strlen (logical_ops[logic]); while (pos[0] == ' ') { pos++; } tmp_value = eval_expression_condition (pos, eval_context); rc = eval_is_true (tmp_value); if (tmp_value) free (tmp_value); value = strdup ((rc) ? EVAL_STR_TRUE : EVAL_STR_FALSE); goto end; } } /* * search for a comparison, and if one is found: * - split expression into two sub-expressions * - evaluate the two sub-expressions * - compare sub-expressions * - return result */ for (comp = 0; comp < EVAL_NUM_COMPARISONS; comp++) { pos = eval_strstr_level (expr2, comparisons[comp], eval_context, "(", ")", 0); if (pos >= expr2) { if (pos > expr2) { pos_end = pos - 1; while ((pos_end > expr2) && (pos_end[0] == ' ')) { pos_end--; } sub_expr = string_strndup (expr2, pos_end + 1 - expr2); } else { sub_expr = strdup (""); } if (!sub_expr) goto end; pos += strlen (comparisons[comp]); while (pos[0] == ' ') { pos++; } if ((comp == EVAL_COMPARE_REGEX_MATCHING) || (comp == EVAL_COMPARE_REGEX_NOT_MATCHING)) { /* for regex: just replace vars in both expressions */ tmp_value = eval_replace_vars (sub_expr, eval_context); tmp_value2 = eval_replace_vars (pos, eval_context); } else { /* other comparison: fully evaluate both expressions */ tmp_value = eval_expression_condition (sub_expr, eval_context); tmp_value2 = eval_expression_condition (pos, eval_context); } free (sub_expr); value = eval_compare (tmp_value, comp, tmp_value2, eval_context); if (tmp_value) free (tmp_value); if (tmp_value2) free (tmp_value2); goto end; } } /* * evaluate sub-expressions between parentheses and replace them with their * value */ while (expr2[0] == '(') { level = 0; pos = expr2 + 1; while (pos[0]) { if (pos[0] == '(') level++; else if (pos[0] == ')') { if (level == 0) break; level--; } pos++; } /* closing parenthesis not found */ if (pos[0] != ')') goto end; sub_expr = string_strndup (expr2 + 1, pos - expr2 - 1); if (!sub_expr) goto end; tmp_value = eval_expression_condition (sub_expr, eval_context); free (sub_expr); if (!pos[1]) { /* * nothing around parentheses, then return value of * sub-expression as-is */ value = tmp_value; goto end; } length = ((tmp_value) ? strlen (tmp_value) : 0) + 1 + strlen (pos + 1) + 1; tmp_value2 = malloc (length); if (!tmp_value2) { if (tmp_value) free (tmp_value); goto end; } tmp_value2[0] = '\0'; if (tmp_value) strcat (tmp_value2, tmp_value); strcat (tmp_value2, " "); strcat (tmp_value2, pos + 1); free (expr2); expr2 = tmp_value2; if (tmp_value) free (tmp_value); } /* * at this point, there is no more logical operator neither comparison, * so we just replace variables in string and return the result */ value = eval_replace_vars (expr2, eval_context); end: if (expr2) free (expr2); return value; } /* * Replaces text in a string using a regular expression and replacement text. * * The argument "regex" is a pointer to a regex compiled with WeeChat function * string_regcomp (or function regcomp). * * The argument "replace" is evaluated and can contain any valid expression, * and these ones: * ${re:0} .. ${re:99} match 0 to 99 (0 is whole match, 1 .. 99 are groups * captured) * ${re:+} the last match (with highest number) * * Examples: * * string | regex | replace | result * ----------+---------------+----------------------------+------------- * test foo | test | Z | Z foo * test foo | ^(test +)(.*) | ${re:2} | foo * test foo | ^(test +)(.*) | ${re:1}/ ${hide:*,${re:2}} | test / *** * test foo | ^(test +)(.*) | ${hide:%,${re:+}} | %%% * * Note: result must be freed after use. */ char * eval_replace_regex (const char *string, regex_t *regex, const char *replace, struct t_eval_context *eval_context) { char *result, *result2, *str_replace; int length, length_replace, start_offset, i, rc, end; int empty_replace_allowed; struct t_eval_regex eval_regex; EVAL_DEBUG("eval_replace_regex(\"%s\", 0x%lx, \"%s\")", string, regex, replace); if (!string || !regex || !replace) return NULL; length = strlen (string) + 1; result = malloc (length); if (!result) return NULL; snprintf (result, length, "%s", string); eval_context->regex = &eval_regex; start_offset = 0; /* we allow one empty replace if input string is empty */ empty_replace_allowed = (result[0]) ? 0 : 1; while (result) { for (i = 0; i < 100; i++) { eval_regex.match[i].rm_so = -1; } rc = regexec (regex, result + start_offset, 100, eval_regex.match, 0); /* no match found: exit the loop */ if ((rc != 0) || (eval_regex.match[0].rm_so < 0)) break; /* * if empty string is matching, continue only if empty replace is * still allowed (to prevent infinite loop) */ if (eval_regex.match[0].rm_eo <= 0) { if (!empty_replace_allowed) break; empty_replace_allowed = 0; } /* adjust the start/end offsets */ eval_regex.last_match = 0; for (i = 0; i < 100; i++) { if (eval_regex.match[i].rm_so >= 0) { eval_regex.last_match = i; eval_regex.match[i].rm_so += start_offset; eval_regex.match[i].rm_eo += start_offset; } } /* check if the regex matched the end of string */ end = !result[eval_regex.match[0].rm_eo]; eval_regex.result = result; str_replace = eval_replace_vars (replace, eval_context); length_replace = (str_replace) ? strlen (str_replace) : 0; length = eval_regex.match[0].rm_so + length_replace + strlen (result + eval_regex.match[0].rm_eo) + 1; result2 = malloc (length); if (!result2) { free (result); return NULL; } result2[0] = '\0'; if (eval_regex.match[0].rm_so > 0) { memcpy (result2, result, eval_regex.match[0].rm_so); result2[eval_regex.match[0].rm_so] = '\0'; } if (str_replace) strcat (result2, str_replace); strcat (result2, result + eval_regex.match[0].rm_eo); free (result); result = result2; if (str_replace) free (str_replace); if (end) break; start_offset = eval_regex.match[0].rm_so + length_replace; if (!result[start_offset]) break; } return result; } /* * Evaluates an expression. * * The hashtable "pointers" must have string for keys, pointer for values. * The hashtable "extra_vars" must have string for keys and values. * The hashtable "options" must have string for keys and values. * * Supported options: * - prefix: change the default prefix before variables to replace ("${") * - suffix: change the default suffix after variables to replace ('}") * - type: * - condition: evaluate as a condition (use operators/parentheses, * return a boolean) * * If the expression is a condition, it can contain: * - conditions: == != < <= > >= * - logical operators: && || * - parentheses for priority * * Examples of simple expression without condition (the [ ] are NOT part of * result): * >> ${window.buffer.number} * == [2] * >> buffer:${window.buffer.full_name} * == [buffer:irc.freenode.#weechat] * >> ${window.win_width} * == [112] * >> ${window.win_height} * == [40] * * Examples of conditions: * >> ${window.buffer.full_name} == irc.freenode.#weechat * == [1] * >> ${window.buffer.full_name} == irc.freenode.#test * == [0] * >> ${window.win_width} >= 30 && ${window.win_height} >= 20 * == [1] * * Note: result must be freed after use (if not NULL). */ char * eval_expression (const char *expr, struct t_hashtable *pointers, struct t_hashtable *extra_vars, struct t_hashtable *options) { struct t_eval_context context, *eval_context; int condition, rc, pointers_allocated, regex_allocated; int ptr_window_added, ptr_buffer_added; char *value; const char *default_prefix = EVAL_DEFAULT_PREFIX; const char *default_suffix = EVAL_DEFAULT_SUFFIX; const char *ptr_value, *regex_replace; struct t_gui_window *window; regex_t *regex; if (!expr) return NULL; condition = 0; pointers_allocated = 0; regex_allocated = 0; regex = NULL; regex_replace = NULL; ptr_window_added = 0; ptr_buffer_added = 0; if (pointers) { regex = (regex_t *)hashtable_get (pointers, "regex"); } else { /* create hashtable pointers if it's NULL */ pointers = hashtable_new (32, WEECHAT_HASHTABLE_STRING, WEECHAT_HASHTABLE_POINTER, NULL, NULL); if (!pointers) return NULL; pointers_allocated = 1; } eval_context = &context; eval_context->pointers = pointers; eval_context->extra_vars = extra_vars; eval_context->extra_vars_eval = 0; eval_context->prefix = default_prefix; eval_context->suffix = default_suffix; eval_context->regex = NULL; eval_context->recursion_count = 0; eval_context->debug = NULL; /* * set window/buffer with pointer to current window/buffer * (if not already defined in the hashtable) */ if (gui_current_window) { if (!hashtable_has_key (pointers, "window")) { hashtable_set (pointers, "window", gui_current_window); ptr_window_added = 1; } if (!hashtable_has_key (pointers, "buffer")) { window = (struct t_gui_window *)hashtable_get (pointers, "window"); if (window) { hashtable_set (pointers, "buffer", window->buffer); ptr_buffer_added = 1; } } } /* read options */ if (options) { /* check the type of evaluation */ ptr_value = hashtable_get (options, "type"); if (ptr_value && (strcmp (ptr_value, "condition") == 0)) condition = 1; /* check if extra vars must be evaluated */ ptr_value = hashtable_get (options, "extra"); if (ptr_value && (strcmp (ptr_value, "eval") == 0)) eval_context->extra_vars_eval = 1; /* check for custom prefix */ ptr_value = hashtable_get (options, "prefix"); if (ptr_value && ptr_value[0]) eval_context->prefix = ptr_value; /* check for custom suffix */ ptr_value = hashtable_get (options, "suffix"); if (ptr_value && ptr_value[0]) eval_context->suffix = ptr_value; /* check for regex */ ptr_value = hashtable_get (options, "regex"); if (ptr_value) { regex = malloc (sizeof (*regex)); if (string_regcomp (regex, ptr_value, REG_EXTENDED | REG_ICASE) == 0) { regex_allocated = 1; } else { free (regex); regex = NULL; } } /* check for regex replacement (evaluated later) */ ptr_value = hashtable_get (options, "regex_replace"); if (ptr_value) { regex_replace = ptr_value; } /* check for debug */ if (hashtable_has_key (options, "debug")) eval_context->debug = string_dyn_alloc (256); } EVAL_DEBUG("eval_expression(\"%s\")", expr); /* evaluate expression */ if (condition) { /* evaluate as condition (return a boolean: "0" or "1") */ value = eval_expression_condition (expr, eval_context); rc = eval_is_true (value); if (value) free (value); value = strdup ((rc) ? EVAL_STR_TRUE : EVAL_STR_FALSE); } else { if (regex && regex_replace) { /* replace with regex */ value = eval_replace_regex (expr, regex, regex_replace, eval_context); } else { /* only replace variables in expression */ value = eval_replace_vars (expr, eval_context); } } if (pointers_allocated) { hashtable_free (pointers); } else { if (ptr_window_added) hashtable_remove (pointers, "window"); if (ptr_buffer_added) hashtable_remove (pointers, "buffer"); } if (regex && regex_allocated) { regfree (regex); free (regex); } if (options && eval_context->debug) hashtable_set (options, "debug_output", *(eval_context->debug)); if (eval_context->debug) string_dyn_free (eval_context->debug, 1); return value; }