shell_var.c 11 KB

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  1. /*
  2. * shell_var.c
  3. */
  4. #include <stdlib.h>
  5. #include <assert.h>
  6. #include <string.h>
  7. #include <ctype.h>
  8. #include "lub/string.h"
  9. #include "private.h"
  10. /*----------------------------------------------------------- */
  11. /*
  12. * search the current viewid string for a variable
  13. */
  14. void clish_shell__expand_viewid(const char *viewid, lub_bintree_t *tree,
  15. clish_context_t *context)
  16. {
  17. char *expanded;
  18. char *q, *saveptr;
  19. expanded = clish_shell_expand(viewid, SHELL_VAR_NONE, context);
  20. if (!expanded)
  21. return;
  22. for (q = strtok_r(expanded, ";", &saveptr);
  23. q; q = strtok_r(NULL, ";", &saveptr)) {
  24. char *value;
  25. clish_var_t *var;
  26. value = strchr(q, '=');
  27. if (!value)
  28. continue;
  29. *value = '\0';
  30. value++;
  31. /* Create var instance */
  32. var = clish_var_new(q);
  33. lub_bintree_insert(tree, var);
  34. clish_var__set_value(var, value);
  35. }
  36. lub_string_free(expanded);
  37. }
  38. /*----------------------------------------------------------- */
  39. /*
  40. * expand context dependent fixed-name variables
  41. */
  42. static char *find_context_var(const char *name, clish_context_t *this)
  43. {
  44. char *result = NULL;
  45. clish_shell_t *shell = this->shell;
  46. if (!lub_string_nocasecmp(name, "__width")) {
  47. char tmp[5];
  48. snprintf(tmp, sizeof(tmp), "%u",
  49. tinyrl__get_width(shell->tinyrl));
  50. tmp[sizeof(tmp) - 1] = '\0';
  51. result = strdup(tmp);
  52. } else if (!lub_string_nocasecmp(name, "__height")) {
  53. char tmp[5];
  54. snprintf(tmp, sizeof(tmp), "%u",
  55. tinyrl__get_height(shell->tinyrl));
  56. tmp[sizeof(tmp) - 1] = '\0';
  57. result = strdup(tmp);
  58. } else if (!lub_string_nocasecmp(name, "__watchdog_timeout")) {
  59. char tmp[5];
  60. snprintf(tmp, sizeof(tmp), "%u", shell->wdog_timeout);
  61. tmp[sizeof(tmp) - 1] = '\0';
  62. result = strdup(tmp);
  63. } else if (!this->cmd) { /* The vars dependent on command */
  64. return NULL;
  65. } else if (!lub_string_nocasecmp(name, "__full_cmd")) {
  66. result = lub_string_dup(clish_command__get_name(this->cmd));
  67. } else if (!lub_string_nocasecmp(name, "__cmd")) {
  68. result = lub_string_dup(clish_command__get_name(
  69. clish_command__get_cmd(this->cmd)));
  70. } else if (!lub_string_nocasecmp(name, "__orig_cmd")) {
  71. result = lub_string_dup(clish_command__get_name(
  72. clish_command__get_orig(this->cmd)));
  73. } else if (!lub_string_nocasecmp(name, "__line")) {
  74. result = clish_shell__get_line(this);
  75. } else if (!lub_string_nocasecmp(name, "__full_line")) {
  76. result = clish_shell__get_full_line(this);
  77. } else if (!lub_string_nocasecmp(name, "__params")) {
  78. if (this->pargv)
  79. result = clish_shell__get_params(this);
  80. } else if (!lub_string_nocasecmp(name, "__interactive")) {
  81. if (clish_shell__get_interactive(this->shell))
  82. result = strdup("1");
  83. else
  84. result = strdup("0");
  85. } else if (lub_string_nocasestr(name, "__prefix") == name) {
  86. int idx = 0;
  87. int pnum = 0;
  88. pnum = lub_argv_wordcount(clish_command__get_name(this->cmd)) -
  89. lub_argv_wordcount(clish_command__get_name(
  90. clish_command__get_cmd(this->cmd)));
  91. idx = atoi(name + strlen("__prefix"));
  92. if (idx < pnum) {
  93. lub_argv_t *argv = lub_argv_new(
  94. clish_command__get_name(this->cmd), 0);
  95. result = lub_string_dup(lub_argv__get_arg(argv, idx));
  96. lub_argv_delete(argv);
  97. }
  98. }
  99. return result;
  100. }
  101. /*--------------------------------------------------------- */
  102. static char *find_var(const char *name, lub_bintree_t *tree, clish_context_t *context)
  103. {
  104. clish_var_t *var = lub_bintree_find(tree, name);
  105. char *value;
  106. bool_t dynamic;
  107. char *res = NULL;
  108. if (!var)
  109. return NULL;
  110. /* Try to get saved value for static var */
  111. dynamic = clish_var__get_dynamic(var);
  112. if (!dynamic) {
  113. char *saved = clish_var__get_saved(var);
  114. if (saved)
  115. return lub_string_dup(saved);
  116. }
  117. /* Try to expand value field */
  118. value = clish_var__get_value(var);
  119. if (value)
  120. res = clish_shell_expand(value, SHELL_VAR_NONE, context);
  121. /* Try to execute ACTION */
  122. if (!res) {
  123. char *out = NULL;
  124. clish_action_t *action = clish_var__get_action(var);
  125. if (clish_shell_exec_action(action, context, &out)) {
  126. lub_string_free(out);
  127. return NULL;
  128. }
  129. res = out;
  130. }
  131. /* Save value for static var */
  132. if (!dynamic && res)
  133. clish_var__set_saved(var, res);
  134. return res;
  135. }
  136. /*--------------------------------------------------------- */
  137. static char *find_global_var(const char *name, clish_context_t *context)
  138. {
  139. return find_var(name, &context->shell->var_tree, context);
  140. }
  141. /*--------------------------------------------------------- */
  142. static char *find_viewid_var(const char *name, clish_context_t *context)
  143. {
  144. int depth = clish_shell__get_depth(context->shell);
  145. if (depth < 0)
  146. return NULL;
  147. return find_var(name, &context->shell->pwdv[depth]->viewid, context);
  148. }
  149. /*--------------------------------------------------------- */
  150. /*
  151. * return the next segment of text from the provided string
  152. * segments are delimited by variables within the string.
  153. */
  154. static char *expand_nextsegment(const char **string, const char *escape_chars,
  155. clish_context_t *this)
  156. {
  157. const char *p = *string;
  158. char *result = NULL;
  159. size_t len = 0;
  160. if (!p)
  161. return NULL;
  162. if (*p && (p[0] == '$') && (p[1] == '{')) {
  163. /* start of a variable */
  164. const char *tmp;
  165. p += 2;
  166. tmp = p;
  167. /*
  168. * find the end of the variable
  169. */
  170. while (*p && p++[0] != '}')
  171. len++;
  172. /* ignore non-terminated variables */
  173. if (p[-1] == '}') {
  174. bool_t valid = BOOL_FALSE;
  175. char *text, *q;
  176. char *saveptr;
  177. /* get the variable text */
  178. text = lub_string_dupn(tmp, len);
  179. /*
  180. * tokenise this INTO ':' separated words
  181. * and either expand or duplicate into the result string.
  182. * Only return a result if at least
  183. * of the words is an expandable variable
  184. */
  185. for (q = strtok_r(text, ":", &saveptr);
  186. q; q = strtok_r(NULL, ":", &saveptr)) {
  187. char *var;
  188. int mod_quote = 0; /* quote modifier */
  189. int mod_esc = 0; /* escape modifier */
  190. char *space;
  191. char *all_esc = NULL;
  192. /* Search for modifiers */
  193. while (*q && !isalpha(*q)) {
  194. if ('#' == *q) {
  195. mod_quote = 1;
  196. mod_esc = 1;
  197. } else if ('\\' == *q)
  198. mod_esc = 1;
  199. else
  200. break;
  201. q++;
  202. }
  203. /* Get clean variable value */
  204. var = clish_shell_expand_var(q, this);
  205. if (!var) {
  206. lub_string_cat(&result, q);
  207. continue;
  208. }
  209. valid = BOOL_TRUE;
  210. /* Quoting */
  211. if (mod_quote)
  212. space = strchr(var, ' ');
  213. if (mod_quote && space)
  214. lub_string_cat(&result, "\"");
  215. /* Internal escaping */
  216. if (mod_esc)
  217. lub_string_cat(&all_esc,
  218. lub_string_esc_quoted);
  219. /* Escape special chars */
  220. if (escape_chars)
  221. lub_string_cat(&all_esc, escape_chars);
  222. if (all_esc) {
  223. char *tstr = lub_string_encode(var,
  224. all_esc);
  225. lub_string_free(var);
  226. var = tstr;
  227. lub_string_free(all_esc);
  228. }
  229. /* copy the expansion or the raw word */
  230. lub_string_cat(&result, var);
  231. /* Quoting */
  232. if (mod_quote && space)
  233. lub_string_cat(&result, "\"");
  234. lub_string_free(var);
  235. }
  236. if (!valid) {
  237. /* not a valid variable expansion */
  238. lub_string_free(result);
  239. result = lub_string_dup("");
  240. }
  241. /* finished with the variable text */
  242. lub_string_free(text);
  243. }
  244. } else {
  245. /* find the start of a variable */
  246. while (*p) {
  247. if ((p[0] == '$') && (p[1] == '{'))
  248. break;
  249. len++;
  250. p++;
  251. }
  252. if (len > 0)
  253. result = lub_string_dupn(*string, len);
  254. }
  255. /* move the string pointer on for next time... */
  256. *string = p;
  257. return result;
  258. }
  259. /*--------------------------------------------------------- */
  260. /*
  261. * This function builds a dynamic string based on that provided
  262. * subtituting each occurance of a "${FRED}" type variable sub-string
  263. * with the appropriate value.
  264. */
  265. char *clish_shell_expand(const char *str, clish_shell_var_t vtype, clish_context_t *context)
  266. {
  267. char *seg, *result = NULL;
  268. const char *escape_chars = NULL;
  269. const clish_command_t *cmd = context->cmd;
  270. /* Escape special characters */
  271. if (SHELL_VAR_REGEX == vtype) {
  272. if (cmd)
  273. escape_chars = clish_command__get_regex_chars(cmd);
  274. if (!escape_chars)
  275. escape_chars = lub_string_esc_regex;
  276. } else if (SHELL_VAR_ACTION == vtype) {
  277. if (cmd)
  278. escape_chars = clish_command__get_escape_chars(cmd);
  279. if (!escape_chars)
  280. escape_chars = lub_string_esc_default;
  281. }
  282. /* read each segment and extend the result */
  283. while ((seg = expand_nextsegment(&str, escape_chars, context))) {
  284. lub_string_cat(&result, seg);
  285. lub_string_free(seg);
  286. }
  287. return result;
  288. }
  289. /*--------------------------------------------------------- */
  290. char *clish_shell__get_params(clish_context_t *context)
  291. {
  292. clish_pargv_t *pargv = context->pargv;
  293. char *line = NULL;
  294. unsigned i, cnt;
  295. const clish_param_t *param;
  296. const clish_parg_t *parg;
  297. char *request = NULL;
  298. if (!pargv)
  299. return NULL;
  300. cnt = clish_pargv__get_count(pargv);
  301. for (i = 0; i < cnt; i++) {
  302. param = clish_pargv__get_param(pargv, i);
  303. if (clish_param__get_hidden(param))
  304. continue;
  305. parg = clish_pargv__get_parg(pargv, i);
  306. if (request)
  307. lub_string_cat(&request, " ");
  308. lub_string_cat(&request, "${#");
  309. lub_string_cat(&request, clish_parg__get_name(parg));
  310. lub_string_cat(&request, "}");
  311. }
  312. line = clish_shell_expand(request, SHELL_VAR_NONE, context);
  313. lub_string_free(request);
  314. return line;
  315. }
  316. /*--------------------------------------------------------- */
  317. static char *internal_get_line(clish_context_t *context, int cmd_type)
  318. {
  319. const clish_command_t *cmd = context->cmd;
  320. clish_pargv_t *pargv = context->pargv;
  321. char *line = NULL;
  322. char *params = NULL;
  323. if (0 == cmd_type) /* __cmd */
  324. lub_string_cat(&line, clish_command__get_name(
  325. clish_command__get_cmd(cmd)));
  326. else /* __full_cmd */
  327. lub_string_cat(&line, clish_command__get_name(cmd));
  328. if (!pargv)
  329. return line;
  330. params = clish_shell__get_params(context);
  331. if (params) {
  332. lub_string_cat(&line, " ");
  333. lub_string_cat(&line, params);
  334. }
  335. lub_string_free(params);
  336. return line;
  337. }
  338. /*--------------------------------------------------------- */
  339. char *clish_shell__get_line(clish_context_t *context)
  340. {
  341. return internal_get_line(context, 0); /* __cmd */
  342. }
  343. /*--------------------------------------------------------- */
  344. char *clish_shell__get_full_line(clish_context_t *context)
  345. {
  346. return internal_get_line(context, 1); /* __full_cmd */
  347. }
  348. /*--------------------------------------------------------- */
  349. char *clish_shell_expand_var(const char *name, clish_context_t *context)
  350. {
  351. clish_shell_t *this;
  352. const clish_command_t *cmd;
  353. clish_pargv_t *pargv;
  354. const char *tmp = NULL;
  355. char *string = NULL;
  356. assert(name);
  357. if (!context)
  358. return NULL;
  359. this = context->shell;
  360. cmd = context->cmd;
  361. pargv = context->pargv;
  362. /* try and substitute a parameter value */
  363. if (pargv) {
  364. const clish_parg_t *parg = clish_pargv_find_arg(pargv, name);
  365. if (parg)
  366. tmp = clish_parg__get_value(parg);
  367. }
  368. /* try and substitute the param's default */
  369. if (!tmp && cmd)
  370. tmp = clish_paramv_find_default(
  371. clish_command__get_paramv(cmd), name);
  372. /* try and substitute a viewId variable */
  373. if (!tmp && this)
  374. tmp = string = find_viewid_var(name, context);
  375. /* try and substitute context fixed variable */
  376. if (!tmp)
  377. tmp = string = find_context_var(name, context);
  378. /* try and substitute a global var value */
  379. if (!tmp && this)
  380. tmp = string = find_global_var(name, context);
  381. /* get the contents of an environment variable */
  382. if (!tmp)
  383. tmp = getenv(name);
  384. if (string)
  385. return string;
  386. return lub_string_dup(tmp);
  387. }
  388. /*----------------------------------------------------------- */