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shell_var.c 14 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 <sys/types.h>
  9. #include <unistd.h>
  10. #include "lub/string.h"
  11. #include "lub/conv.h"
  12. #include "private.h"
  13. /*----------------------------------------------------------- */
  14. /*
  15. * search the current viewid string for a variable
  16. */
  17. void clish_shell__expand_viewid(const char *viewid, lub_bintree_t *tree,
  18. clish_context_t *context)
  19. {
  20. char *expanded;
  21. char *q;
  22. char *saveptr = NULL;
  23. expanded = clish_shell_expand(viewid, SHELL_VAR_NONE, context);
  24. if (!expanded)
  25. return;
  26. for (q = strtok_r(expanded, ";", &saveptr);
  27. q; q = strtok_r(NULL, ";", &saveptr)) {
  28. char *value;
  29. clish_var_t *var;
  30. value = strchr(q, '=');
  31. if (!value)
  32. continue;
  33. *value = '\0';
  34. value++;
  35. /* Create var instance */
  36. var = clish_var_new(q);
  37. lub_bintree_insert(tree, var);
  38. clish_var__set_value(var, value);
  39. }
  40. lub_string_free(expanded);
  41. }
  42. /*----------------------------------------------------------- */
  43. /*
  44. * expand context dependent fixed-name variables
  45. */
  46. static char *find_context_var(const char *name, clish_context_t *this)
  47. {
  48. char *result = NULL;
  49. clish_shell_t *shell = this->shell;
  50. if (!lub_string_nocasecmp(name, "_width")) {
  51. char tmp[5];
  52. snprintf(tmp, sizeof(tmp), "%u",
  53. tinyrl__get_width(shell->tinyrl));
  54. tmp[sizeof(tmp) - 1] = '\0';
  55. result = strdup(tmp);
  56. } else if (!lub_string_nocasecmp(name, "_height")) {
  57. char tmp[5];
  58. snprintf(tmp, sizeof(tmp), "%u",
  59. tinyrl__get_height(shell->tinyrl));
  60. tmp[sizeof(tmp) - 1] = '\0';
  61. result = strdup(tmp);
  62. } else if (!lub_string_nocasecmp(name, "_watchdog_timeout")) {
  63. char tmp[5];
  64. snprintf(tmp, sizeof(tmp), "%u", shell->wdog_timeout);
  65. tmp[sizeof(tmp) - 1] = '\0';
  66. result = strdup(tmp);
  67. } else if (!this->cmd) { /* The vars dependent on command */
  68. return NULL;
  69. } else if (!lub_string_nocasecmp(name, "_full_cmd")) {
  70. result = lub_string_dup(clish_command__get_name(this->cmd));
  71. } else if (!lub_string_nocasecmp(name, "_cmd")) {
  72. result = lub_string_dup(clish_command__get_name(
  73. clish_command__get_cmd(this->cmd)));
  74. } else if (!lub_string_nocasecmp(name, "_orig_cmd")) {
  75. result = lub_string_dup(clish_command__get_name(
  76. clish_command__get_orig(this->cmd)));
  77. } else if (!lub_string_nocasecmp(name, "_line")) {
  78. result = clish_shell__get_line(this);
  79. } else if (!lub_string_nocasecmp(name, "_full_line")) {
  80. result = clish_shell__get_full_line(this);
  81. } else if (!lub_string_nocasecmp(name, "_params")) {
  82. if (this->pargv)
  83. result = clish_shell__get_params(this);
  84. } else if (!lub_string_nocasecmp(name, "_interactive")) {
  85. if (clish_shell__get_interactive(this->shell) &&
  86. tinyrl__get_isatty(this->shell->tinyrl))
  87. result = strdup("1");
  88. else
  89. result = strdup("0");
  90. } else if (!lub_string_nocasecmp(name, "_isatty")) {
  91. if (tinyrl__get_isatty(this->shell->tinyrl))
  92. result = strdup("1");
  93. else
  94. result = strdup("0");
  95. } else if (!lub_string_nocasecmp(name, "_pid")) {
  96. char tmp[10];
  97. snprintf(tmp, sizeof(tmp), "%u", getpid());
  98. tmp[sizeof(tmp) - 1] = '\0';
  99. result = strdup(tmp);
  100. } else if (lub_string_nocasestr(name, "_prefix") == name) {
  101. unsigned int idx = 0;
  102. unsigned int pnum = 0;
  103. pnum = lub_string_wordcount(clish_command__get_name(this->cmd)) -
  104. lub_string_wordcount(clish_command__get_name(
  105. clish_command__get_cmd(this->cmd)));
  106. lub_conv_atoui(name + strlen("_prefix"), &idx, 0);
  107. if (idx < pnum) {
  108. lub_argv_t *argv = lub_argv_new(
  109. clish_command__get_name(this->cmd), 0);
  110. result = lub_string_dup(lub_argv__get_arg(argv, idx));
  111. lub_argv_delete(argv);
  112. }
  113. } else if (!lub_string_nocasecmp(name, "_cur_depth")) {
  114. char tmp[10];
  115. int depth = clish_shell__get_depth(shell);
  116. snprintf(tmp, sizeof(tmp), "%u", depth);
  117. tmp[sizeof(tmp) - 1] = '\0';
  118. result = strdup(tmp);
  119. } else if (!lub_string_nocasecmp(name, "_cur_pwd")) {
  120. int depth = clish_shell__get_depth(shell);
  121. result = clish_shell__get_pwd_full(shell, depth);
  122. }
  123. return result;
  124. }
  125. /*--------------------------------------------------------- */
  126. static char *find_var(const char *name, lub_bintree_t *tree, clish_context_t *context)
  127. {
  128. clish_var_t *var = lub_bintree_find(tree, name);
  129. const char *value;
  130. bool_t dynamic;
  131. char *res = NULL;
  132. if (!var)
  133. return NULL;
  134. /* Try to get saved value for static var */
  135. dynamic = clish_var__get_dynamic(var);
  136. if (!dynamic) {
  137. const char *saved = clish_var__get_saved(var);
  138. if (saved)
  139. return lub_string_dup(saved);
  140. }
  141. /* Try to expand value field */
  142. value = clish_var__get_value(var);
  143. if (value)
  144. res = clish_shell_expand(value, SHELL_VAR_NONE, context);
  145. /* Try to execute ACTION */
  146. if (!res) {
  147. char *out = NULL;
  148. clish_context_t ctx;
  149. clish_context_dup(&ctx, context);
  150. clish_context__set_action(&ctx, clish_var__get_action(var));
  151. if (clish_shell_exec_action(&ctx, &out, BOOL_FALSE)) {
  152. lub_string_free(out);
  153. return NULL;
  154. }
  155. res = out;
  156. }
  157. /* Save value for static var */
  158. if (!dynamic && res)
  159. clish_var__set_saved(var, res);
  160. return res;
  161. }
  162. /*--------------------------------------------------------- */
  163. static char *find_global_var(const char *name, clish_context_t *context)
  164. {
  165. clish_shell_t *shell = clish_context__get_shell(context);
  166. return find_var(name, &shell->var_tree, context);
  167. }
  168. /*--------------------------------------------------------- */
  169. static char *find_viewid_var(const char *name, clish_context_t *context)
  170. {
  171. clish_shell_t *shell = clish_context__get_shell(context);
  172. int depth = clish_shell__get_depth(shell);
  173. if (depth < 0)
  174. return NULL;
  175. return find_var(name, &shell->pwdv[depth]->viewid, context);
  176. }
  177. static char * chardiff(const char *syms, const char *minus)
  178. {
  179. char *dst = malloc(strlen(syms) + 1);
  180. char *p = dst;
  181. const char *src;
  182. for (src = syms; *src; src++) {
  183. if (!strchr(minus, *src))
  184. *(p++) = *src;
  185. }
  186. *p = '\0';
  187. return dst;
  188. }
  189. /*--------------------------------------------------------- */
  190. /*
  191. * return the next segment of text from the provided string
  192. * segments are delimited by variables within the string.
  193. */
  194. static char *expand_nextsegment(const char **string, const char *escape_chars,
  195. clish_context_t *this)
  196. {
  197. const char *p = *string;
  198. char *result = NULL;
  199. size_t len = 0;
  200. if (!p)
  201. return NULL;
  202. if (*p && (p[0] == '$') && (p[1] == '{')) {
  203. /* start of a variable */
  204. const char *tmp;
  205. p += 2;
  206. tmp = p;
  207. /*
  208. * find the end of the variable
  209. */
  210. while (*p && p++[0] != '}')
  211. len++;
  212. /* ignore non-terminated variables */
  213. if (p[-1] == '}') {
  214. bool_t valid = BOOL_FALSE;
  215. char *text, *q;
  216. char *saveptr = NULL;
  217. /* get the variable text */
  218. text = lub_string_dupn(tmp, len);
  219. /*
  220. * tokenise this INTO ':' separated words
  221. * and either expand or duplicate into the result string.
  222. * Only return a result if at least
  223. * of the words is an expandable variable
  224. */
  225. for (q = strtok_r(text, ":", &saveptr);
  226. q; q = strtok_r(NULL, ":", &saveptr)) {
  227. char *var;
  228. int mod_quote = 0; /* quote modifier */
  229. int mod_esc = 0; /* internal escape modifier */
  230. int mod_esc_chars = 1; /* escaping */
  231. int mod_esc_dec = 0; /* remove internal chars from escaping */
  232. char *space;
  233. char *all_esc = NULL;
  234. /* Search for modifiers */
  235. while (*q && !isalpha(*q)) {
  236. if ('#' == *q) {
  237. mod_quote = 1;
  238. mod_esc = 1;
  239. } else if ('\\' == *q) {
  240. mod_esc = 1;
  241. } else if ('!' == *q) {
  242. mod_quote = 1;
  243. mod_esc = 1;
  244. mod_esc_chars = 0;
  245. } else if ('~' == *q) {
  246. mod_esc = 1;
  247. mod_esc_chars = 0;
  248. /* Internal automatic variable like ${__line} */
  249. } else if (('_' == *q) && ('_' == *(q+1))) {
  250. mod_esc_dec = 1;
  251. q++;
  252. break;
  253. /* No escaping at all. Usefull for macros VAR */
  254. } else if ('^' == *q) {
  255. mod_quote = 0;
  256. mod_esc = 0;
  257. mod_esc_chars = 0;
  258. } else
  259. break;
  260. q++;
  261. }
  262. /* Get clean variable value */
  263. var = clish_shell_expand_var(q, this);
  264. if (!var) {
  265. lub_string_cat(&result, q);
  266. continue;
  267. }
  268. valid = BOOL_TRUE;
  269. /* Quoting */
  270. if (mod_quote)
  271. space = strchr(var, ' ');
  272. if (mod_quote && space)
  273. lub_string_cat(&result, "\"");
  274. /* Escape special chars */
  275. if (escape_chars && mod_esc_chars) {
  276. /* Remove internal esc from escape chars */
  277. if (mod_esc_dec)
  278. all_esc = chardiff(escape_chars,
  279. lub_string_esc_quoted);
  280. else
  281. all_esc = lub_string_dup(escape_chars);
  282. }
  283. /* Internal escaping */
  284. if (mod_esc)
  285. lub_string_cat(&all_esc,
  286. lub_string_esc_quoted);
  287. /* Real escaping */
  288. if (all_esc) {
  289. char *tstr = lub_string_encode(var,
  290. all_esc);
  291. lub_string_free(var);
  292. var = tstr;
  293. lub_string_free(all_esc);
  294. }
  295. /* copy the expansion or the raw word */
  296. lub_string_cat(&result, var);
  297. /* Quoting */
  298. if (mod_quote && space)
  299. lub_string_cat(&result, "\"");
  300. lub_string_free(var);
  301. }
  302. if (!valid) {
  303. /* not a valid variable expansion */
  304. lub_string_free(result);
  305. result = lub_string_dup("");
  306. }
  307. /* finished with the variable text */
  308. lub_string_free(text);
  309. }
  310. } else {
  311. /* find the start of a variable */
  312. while (*p) {
  313. if ((p[0] == '$') && (p[1] == '{'))
  314. break;
  315. len++;
  316. p++;
  317. }
  318. if (len > 0)
  319. result = lub_string_dupn(*string, len);
  320. }
  321. /* move the string pointer on for next time... */
  322. *string = p;
  323. return result;
  324. }
  325. /*--------------------------------------------------------- */
  326. /*
  327. * This function builds a dynamic string based on that provided
  328. * subtituting each occurance of a "${FRED}" type variable sub-string
  329. * with the appropriate value.
  330. */
  331. char *clish_shell_expand(const char *str, clish_shell_var_e vtype, clish_context_t *context)
  332. {
  333. char *seg, *result = NULL;
  334. const char *escape_chars = NULL;
  335. const clish_command_t *cmd = clish_context__get_cmd(context);
  336. /* Escape special characters */
  337. if (SHELL_VAR_REGEX == vtype) {
  338. if (cmd)
  339. escape_chars = clish_command__get_regex_chars(cmd);
  340. if (!escape_chars)
  341. escape_chars = lub_string_esc_regex;
  342. } else if (SHELL_VAR_ACTION == vtype) {
  343. if (cmd)
  344. escape_chars = clish_command__get_escape_chars(cmd);
  345. if (!escape_chars)
  346. escape_chars = lub_string_esc_default;
  347. }
  348. /* read each segment and extend the result */
  349. while ((seg = expand_nextsegment(&str, escape_chars, context))) {
  350. lub_string_cat(&result, seg);
  351. lub_string_free(seg);
  352. }
  353. return result;
  354. }
  355. /*--------------------------------------------------------- */
  356. char *clish_shell__get_params(clish_context_t *context)
  357. {
  358. clish_pargv_t *pargv = clish_context__get_pargv(context);
  359. char *line = NULL;
  360. unsigned i, cnt;
  361. const clish_param_t *param;
  362. const clish_parg_t *parg;
  363. char *request = NULL;
  364. if (!pargv)
  365. return NULL;
  366. cnt = clish_pargv__get_count(pargv);
  367. for (i = 0; i < cnt; i++) {
  368. param = clish_pargv__get_param(pargv, i);
  369. if (clish_param__get_hidden(param))
  370. continue;
  371. parg = clish_pargv__get_parg(pargv, i);
  372. if (request)
  373. lub_string_cat(&request, " ");
  374. lub_string_cat(&request, "${!");
  375. lub_string_cat(&request, clish_parg__get_name(parg));
  376. lub_string_cat(&request, "}");
  377. }
  378. line = clish_shell_expand(request, SHELL_VAR_NONE, context);
  379. lub_string_free(request);
  380. return line;
  381. }
  382. /*--------------------------------------------------------- */
  383. static char *internal_get_line(clish_context_t *context, int cmd_type)
  384. {
  385. const clish_command_t *cmd = clish_context__get_cmd(context);
  386. clish_pargv_t *pargv = clish_context__get_pargv(context);
  387. char *line = NULL;
  388. char *params = NULL;
  389. if (0 == cmd_type) /* __cmd */
  390. lub_string_cat(&line, clish_command__get_name(
  391. clish_command__get_cmd(cmd)));
  392. else /* __full_cmd */
  393. lub_string_cat(&line, clish_command__get_name(cmd));
  394. if (!pargv)
  395. return line;
  396. params = clish_shell__get_params(context);
  397. if (params) {
  398. lub_string_cat(&line, " ");
  399. lub_string_cat(&line, params);
  400. }
  401. lub_string_free(params);
  402. return line;
  403. }
  404. /*--------------------------------------------------------- */
  405. char *clish_shell__get_line(clish_context_t *context)
  406. {
  407. return internal_get_line(context, 0); /* __cmd */
  408. }
  409. /*--------------------------------------------------------- */
  410. char *clish_shell__get_full_line(clish_context_t *context)
  411. {
  412. return internal_get_line(context, 1); /* __full_cmd */
  413. }
  414. /*--------------------------------------------------------- */
  415. char *clish_shell_expand_var(const char *name, clish_context_t *context)
  416. {
  417. return clish_shell_expand_var_ex(name, context, SHELL_EXPAND_ALL);
  418. }
  419. /*----------------------------------------------------------- */
  420. char *clish_shell_expand_var_ex(const char *name, clish_context_t *context, clish_shell_expand_e flags)
  421. {
  422. clish_shell_t *this;
  423. const clish_command_t *cmd;
  424. clish_pargv_t *pargv;
  425. const char *tmp = NULL;
  426. char *string = NULL;
  427. assert(name);
  428. if (!context)
  429. return NULL;
  430. this = clish_context__get_shell(context);
  431. cmd = clish_context__get_cmd(context);
  432. pargv = clish_context__get_pargv(context);
  433. /* try and substitute a parameter value */
  434. if (pargv && (flags & SHELL_EXPAND_PARAM)) {
  435. const clish_parg_t *parg = clish_pargv_find_arg(pargv, name);
  436. if (parg)
  437. tmp = clish_parg__get_value(parg);
  438. }
  439. /* try and substitute the param's default */
  440. if (!tmp && cmd && (flags & SHELL_EXPAND_PARAM))
  441. tmp = clish_paramv_find_default(
  442. clish_command__get_paramv(cmd), name);
  443. /* try and substitute a viewId variable */
  444. if (!tmp && this && (flags & SHELL_EXPAND_VIEW))
  445. tmp = string = find_viewid_var(name, context);
  446. /* try and substitute context fixed variable */
  447. if (!tmp && (flags & SHELL_EXPAND_CONTEXT))
  448. tmp = string = find_context_var(name, context);
  449. /* try and substitute a global var value */
  450. if (!tmp && this && (flags & SHELL_EXPAND_VAR))
  451. tmp = string = find_global_var(name, context);
  452. /* get the contents of an environment variable */
  453. if (!tmp && (flags & SHELL_EXPAND_ENV))
  454. tmp = getenv(name);
  455. if (string)
  456. return string;
  457. return lub_string_dup(tmp);
  458. }
  459. /*----------------------------------------------------------- */