mdw@git.distorted.org.uk Git - runlisp/blob - common.c

   1 /* -*-c-*-
   2  *
   3  * Common functionality of a less principled nature
   4  *
   5  * (c) 2020 Mark Wooding
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Runlisp, a tool for invoking Common Lisp scripts.
  11  *
  12  * Runlisp is free software: you can redistribute it and/or modify it
  13  * under the terms of the GNU General Public License as published by the
  14  * Free Software Foundation; either version 3 of the License, or (at your
  15  * option) any later version.
  16  *
  17  * Runlisp is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with Runlisp.  If not, see <https://www.gnu.org/licenses/>.
  24  */
  25
  26 /*----- Header files ------------------------------------------------------*/
  27
  28 #include "config.h"
  29
  30 #include <assert.h>
  31 #include <ctype.h>
  32 #include <errno.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35
  36 #include <dirent.h>
  37 #include <pwd.h>
  38 #include <unistd.h>
  39
  40 #include <sys/stat.h>
  41
  42 #include "common.h"
  43 #include "lib.h"
  44
  45 /*----- Public variables --------------------------------------------------*/
  46
  47 struct config config = CONFIG_INIT;
  48 struct config_section *toplevel, *builtin, *common, *env;
  49 unsigned verbose = 1;
  50
  51 /*----- Internal utilities ------------------------------------------------*/
  52
  53 static void escapify(struct dstr *d, const char *p)
  54 {
  55   size_t n;
  56
  57   for (;;) {
  58     n = strcspn(p, "\"'\\");
  59     if (n) { dstr_putm(d, p, n); p += n; }
  60     if (!*p) break;
  61     dstr_putc(d, '\\'); dstr_putc(d, *p++);
  62   }
  63   dstr_putz(d);
  64 }
  65
  66 static void homedir(struct dstr *d)
  67 {
  68   static const char *home = 0;
  69   const char *p;
  70   struct passwd *pw;
  71
  72   if (!home) {
  73     p = my_getenv("HOME", 0);
  74     if (p) home = p;
  75     else {
  76       pw = getpwuid(getuid());
  77       if (!pw) lose("can't find user in password database");
  78       home = xstrdup(pw->pw_dir);
  79     }
  80   }
  81   dstr_puts(d, home);
  82 }
  83
  84 static void user_config_dir(struct dstr *d)
  85 {
  86   const char *p;
  87
  88   p = my_getenv("XDG_CONFIG_HOME", 0);
  89   if (p) dstr_puts(d, p);
  90   else { homedir(d); dstr_puts(d, "/.config"); }
  91 }
  92
  93 /*----- Miscellany --------------------------------------------------------*/
  94
  95 const char *my_getenv(const char *name, const char *dflt)
  96 {
  97   struct config_var *var;
  98
  99   var = config_find_var(&config, env, 0, name);
 100   return (var ? var->val : dflt);
 101 }
 102
 103 long parse_int(const char *what, const char *p, long min, long max)
 104 {
 105   long n;
 106   int oerr = errno;
 107   char *q;
 108
 109   errno = 0;
 110   n = strtol(p, &q, 0);
 111   while (ISSPACE(*q)) q++;
 112   if (errno || *q) lose("invalid %s `%s'", what, p);
 113   if (n < min || n > max)
 114     lose("%s %ld out of range (must be between %ld and %ld)",
 115          what, n, min, max);
 116   errno = oerr;
 117   return (n);
 118 }
 119
 120 void argv_string(struct dstr *d, const struct argv *av)
 121 {
 122   size_t i;
 123
 124   for (i = 0; i < av->n; i++) {
 125     if (i) { dstr_putc(d, ','); dstr_putc(d, ' '); }
 126     dstr_putc(d, '`'); escapify(d, av->v[i]); dstr_putc(d, '\'');
 127   }
 128   dstr_putz(d);
 129 }
 130
 131 /*----- File utilities ----------------------------------------------------*/
 132
 133 int file_exists_p(const char *path, unsigned f)
 134 {
 135   struct stat st;
 136
 137   if (stat(path, &st)) {
 138     if (f&FEF_VERBOSE) moan("file `%s' not found", path);
 139     return (0);
 140   } else if (!(S_ISREG(st.st_mode))) {
 141     if (f&FEF_VERBOSE) moan("`%s' is not a regular file", path);
 142     return (0);
 143   } else if ((f&FEF_EXEC) && access(path, X_OK)) {
 144     if (f&FEF_VERBOSE) moan("file `%s' is not executable", path);
 145     return (0);
 146   } else {
 147     if (f&FEF_VERBOSE) moan("found file `%s'", path);
 148     return (1);
 149   }
 150 }
 151
 152 int found_in_path_p(const char *prog, unsigned f)
 153 {
 154   struct dstr p = DSTR_INIT, d = DSTR_INIT;
 155   const char *path;
 156   char *q;
 157   size_t n, avail, proglen;
 158   int i, rc;
 159
 160   if (strchr(prog, '/'))
 161     return (file_exists_p(prog, f));
 162   path = my_getenv("PATH", 0);
 163   if (path)
 164     dstr_puts(&p, path);
 165   else {
 166     dstr_puts(&p, ".:");
 167     i = 0;
 168   again:
 169     avail = p.sz - p.len;
 170     n = confstr(_CS_PATH, p.p + p.len, avail);
 171     if (avail > n) { i++; assert(i < 2); dstr_ensure(&p, n); goto again; }
 172   }
 173
 174   q = p.p; proglen = strlen(prog);
 175   for (;;) {
 176     n = strcspn(q, ":");
 177     dstr_reset(&d);
 178     if (n) dstr_putm(&d, q, n);
 179     else dstr_putc(&d, '.');
 180     dstr_putc(&d, '/');
 181     dstr_putm(&d, prog, proglen);
 182     dstr_putz(&d);
 183     if (file_exists_p(d.p, verbose >= 4 ? f : f&~FEF_VERBOSE)) {
 184       if (verbose == 2) moan("found program `%s'", d.p);
 185       rc = 1; goto end;
 186     }
 187     q += n; if (!*q) break; else q++;
 188   }
 189
 190   rc = 0;
 191 end:
 192   dstr_release(&p); dstr_release(&d);
 193   return (rc);
 194 }
 195
 196 int try_exec(struct argv *av, unsigned f)
 197 {
 198   struct dstr d = DSTR_INIT;
 199   int rc;
 200
 201   assert(av->n); argv_appendz(av);
 202   if (verbose >= 2) { argv_string(&d, av); moan("trying %s...", d.p); }
 203   if (f&TEF_DRYRUN) {
 204     if (found_in_path_p(av->v[0], f&TEF_VERBOSE ? FEF_VERBOSE : 0))
 205       { rc = 0; goto end; }
 206   } else {
 207     execvp(av->v[0], (/*unconst*/ char **)av->v);
 208     if (errno != ENOENT) {
 209       moan("failed to exec `%s': %s", av->v[0], strerror(errno));
 210       _exit(2);
 211     }
 212   }
 213
 214   if (verbose >= 2) moan("`%s' not found", av->v[0]);
 215   rc = -1;
 216 end:
 217   dstr_release(&d);
 218   return (rc);
 219 }
 220
 221 /*----- Configuration -----------------------------------------------------*/
 222
 223 void read_config_file(const char *what, const char *file, unsigned f)
 224 {
 225   if (!config_read_file(&config, file, f)) {
 226     if (verbose >= 2)
 227       moan("read %s configuration file `%s'", what, file);
 228   } else {
 229     if (verbose >= 3)
 230       moan("ignoring missing %s configuration file `%s'", what, file);
 231   }
 232 }
 233
 234 static int order_strings(const void *xx, const void *yy)
 235   { const char *const *x = xx, *const *y = yy; return (strcmp(*x, *y)); }
 236
 237 void read_config_dir(const char *what, const char *path, unsigned f)
 238 {
 239   struct argv av = ARGV_INIT;
 240   struct dstr dd = DSTR_INIT;
 241   struct stat st;
 242   DIR *dir;
 243   struct dirent *d;
 244   size_t i, n, len;
 245
 246   dir = opendir(path);
 247   if (!dir) {
 248     if (!(f&CF_NOENTOK) || errno != ENOENT)
 249       lose("failed to read %s configuration directory `%s': %s",
 250            what, path, strerror(errno));
 251     if (verbose >= 3)
 252       moan("ignoring missing %s configuration directory `%s'", what, path);
 253     return;
 254   }
 255
 256   dstr_puts(&dd, path); dstr_putc(&dd, '/'); n = dd.len;
 257   for (;;) {
 258     d = readdir(dir); if (!d) break;
 259     len = strlen(d->d_name);
 260     if (len < 5 || STRCMP(d->d_name + len - 5, !=, ".conf")) continue;
 261     dd.len = n; dstr_putm(&dd, d->d_name, len); dstr_putz(&dd);
 262     if (stat(dd.p, &st))
 263       lose("failed to read file metadata for `%s': %s",
 264            dd.p, strerror(errno));
 265     if (!S_ISREG(st.st_mode)) continue;
 266     argv_append(&av, xstrdup(d->d_name));
 267   }
 268
 269   qsort(av.v, av.n, sizeof(*av.v), order_strings);
 270
 271   for (i = 0; i < av.n; i++) {
 272     dd.len = n; dstr_puts(&dd, av.v[i]);
 273     read_config_file(what, dd.p, f&~CF_NOENTOK);
 274   }
 275
 276   for (i = 0; i < av.n; i++) free((/*unconst*/ char *)av.v[i]);
 277   argv_release(&av); dstr_release(&dd); closedir(dir);
 278   return;
 279 }
 280
 281 void read_config_path(const char *path, unsigned f)
 282 {
 283   struct stat st;
 284
 285   if (!stat(path, &st) && S_ISDIR(st.st_mode))
 286     read_config_dir("command-line specified ", path, f);
 287   else
 288     read_config_file("command-line specified", path, f);
 289 }
 290
 291 int set_config_var(const char *assign)
 292 {
 293   struct config_section *sect;
 294   const char *p, *q;
 295
 296   p = strchr(assign, '=');
 297   if (!p) { moan("missing `=' in option assignment"); return (-1); }
 298   q = strchr(assign, ':');
 299   if (!q || q > p)
 300     { sect = toplevel; q = assign; }
 301   else {
 302     sect = config_find_section_n(&config, CF_CREAT, assign, q - assign);
 303     q++;
 304   }
 305   config_set_var_n(&config, sect, CF_LITERAL | CF_OVERRIDE,
 306                    q, p - q, p + 1, strlen(p + 1));
 307   return (0);
 308 }
 309
 310 void init_config(void)
 311 {
 312   toplevel = config_find_section(&config, CF_CREAT, "@CONFIG");
 313   builtin = config_find_section(&config, CF_CREAT, "@BUILTIN");
 314   common = config_find_section(&config, CF_CREAT, "@COMMON");
 315   env = config_find_section(&config, CF_CREAT, "@ENV");
 316   config_set_fallback(&config, common);
 317   config_set_parent(builtin, 0);
 318   config_set_parent(common, builtin);
 319   config_set_parent(toplevel, 0);
 320   config_read_env(&config, env);
 321
 322   config_set_var(&config, toplevel, CF_LITERAL, "data-dir",
 323                  my_getenv("RUNLISP_DATADIR", DATADIR));
 324   config_set_var(&config, toplevel, CF_LITERAL, "image-dir",
 325                  my_getenv("RUNLISP_IMAGEDIR", IMAGEDIR));
 326
 327 #ifdef ECL_OPTIONS_GNU
 328   config_set_var(&config, builtin, CF_LITERAL, "@ECLOPT", "--");
 329 #else
 330   config_set_var(&config, builtin, CF_LITERAL, "@ECLOPT", "-");
 331 #endif
 332 }
 333
 334 void load_default_config(void)
 335 {
 336   const char *p;
 337   struct dstr d = DSTR_INIT;
 338
 339   p = my_getenv("RUNLISP_SYSCONFIG", ETCDIR "/runlisp.conf");
 340   read_config_file("system", p, 0);
 341   p = my_getenv("RUNLISP_SYSCONFIG_DIR", ETCDIR "/runlisp.d");
 342   read_config_dir("system", p, CF_NOENTOK);
 343   p = my_getenv("RUNLISP_USERCONFIG", 0);
 344   if (p)
 345     read_config_file("user", p, CF_NOENTOK);
 346   else {
 347     dstr_reset(&d); homedir(&d); dstr_puts(&d, "/.runlisp.conf");
 348     read_config_file("user", d.p, CF_NOENTOK);
 349     dstr_reset(&d); user_config_dir(&d); dstr_puts(&d, "/runlisp.conf");
 350     read_config_file("user", d.p, CF_NOENTOK);
 351   }
 352   dstr_release(&d);
 353 }
 354
 355 void dump_config(void)
 356 {
 357   struct config_section_iter si;
 358   struct config_section *sect;
 359   struct config_var_iter vi;
 360   struct config_var *var;
 361   struct dstr d = DSTR_INIT;
 362
 363   for (config_start_section_iter(&config, &si);
 364        (sect = config_next_section(&si)); )
 365     for (config_start_var_iter(sect, &vi);
 366          (var = config_next_var(&vi)); ) {
 367       dstr_reset(&d); escapify(&d, var->val);
 368       moan("config %s:%s = `%s'",
 369            CONFIG_SECTION_NAME(sect), CONFIG_VAR_NAME(var), d.p);
 370     }
 371   dstr_release(&d);
 372 }
 373
 374 /*----- That's all, folks -------------------------------------------------*/