usr/src/boot/sys/boot/common/interp.c

   1 /*-
   2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 /*
  31  * Simple commandline interpreter, toplevel and misc.
  32  *
  33  * XXX may be obsoleted by BootFORTH or some other, better, interpreter.
  34  */
  35
  36 #include <stand.h>
  37 #include <string.h>
  38 #include "bootstrap.h"
  39
  40 #ifdef BOOT_FORTH
  41 #include "ficl.h"
  42 #define RETURN(x)       ficlStackPushInteger(ficlVmGetDataStack(bf_vm),!x); return(x)
  43
  44 extern ficlVm *bf_vm;
  45 #else
  46 #define RETURN(x)       return(x)
  47 #endif
  48
  49 #include "linenoise/linenoise.h"
  50
  51 #define MAXARGS 20              /* maximum number of arguments allowed */
  52
  53 static char *prompt(void);
  54
  55 #ifndef BOOT_FORTH
  56 static int      perform(int argc, char *argv[]);
  57
  58 /*
  59  * Perform the command
  60  */
  61 int
  62 perform(int argc, char *argv[])
  63 {
  64     int                         result;
  65     struct bootblk_command      **cmdp;
  66     bootblk_cmd_t               *cmd;
  67
  68     if (argc < 1)
  69         return(CMD_OK);
  70
  71     /* set return defaults; a successful command will override these */
  72     command_errmsg = command_errbuf;
  73     strcpy(command_errbuf, "no error message");
  74     cmd = NULL;
  75     result = CMD_ERROR;
  76
  77     /* search the command set for the command */
  78     SET_FOREACH(cmdp, Xcommand_set) {
  79         if (((*cmdp)->c_name != NULL) && !strcmp(argv[0], (*cmdp)->c_name))
  80             cmd = (*cmdp)->c_fn;
  81     }
  82     if (cmd != NULL) {
  83         result = (cmd)(argc, argv);
  84     } else {
  85         command_errmsg = "unknown command";
  86     }
  87     RETURN(result);
  88 }
  89 #endif  /* ! BOOT_FORTH */
  90
  91 /*
  92  * Interactive mode
  93  */
  94 void
  95 interact(const char *rc)
  96 {
  97     char *input = NULL;
  98
  99     bf_init((rc) ? "" : NULL);
 100
 101     if (rc == NULL) {
 102         /* Read our default configuration. */
 103         include("/boot/loader.rc");
 104     } else if (*rc != '\0')
 105         include(rc);
 106
 107     printf("\n");
 108
 109     /*
 110      * Before interacting, we might want to autoboot.
 111      */
 112     autoboot_maybe();
 113
 114     /*
 115      * Not autobooting, go manual
 116      */
 117     printf("\nType '?' for a list of commands, 'help' for more detailed help.\n");
 118     if (getenv("prompt") == NULL)
 119         setenv("prompt", "${interpret}", 1);
 120     if (getenv("interpret") == NULL)
 121         setenv("interpret", "ok", 1);
 122
 123
 124     while ((input = linenoise(prompt())) != NULL) {
 125         bf_vm->sourceId.i = 0;
 126         bf_run(input);
 127         linenoiseHistoryAdd(input);
 128         free(input);
 129     }
 130 }
 131
 132 /*
 133  * Read commands from a file, then execute them.
 134  *
 135  * We store the commands in memory and close the source file so that the media
 136  * holding it can safely go away while we are executing.
 137  *
 138  * Commands may be prefixed with '@' (so they aren't displayed) or '-' (so
 139  * that the script won't stop if they fail).
 140  */
 141 COMMAND_SET(include, "include", "read commands from a file", command_include);
 142
 143 static int
 144 command_include(int argc, char *argv[])
 145 {
 146     int         i;
 147     int         res;
 148     char        **argvbuf;
 149
 150     /*
 151      * Since argv is static, we need to save it here.
 152      */
 153     argvbuf = (char**) calloc((u_int)argc, sizeof(char*));
 154     for (i = 0; i < argc; i++)
 155         argvbuf[i] = strdup(argv[i]);
 156
 157     res=CMD_OK;
 158     for (i = 1; (i < argc) && (res == CMD_OK); i++)
 159         res = include(argvbuf[i]);
 160
 161     for (i = 0; i < argc; i++)
 162         free(argvbuf[i]);
 163     free(argvbuf);
 164
 165     return(res);
 166 }
 167
 168 /*
 169  * Header prepended to each line. The text immediately follows the header.
 170  * We try to make this short in order to save memory -- the loader has
 171  * limited memory available, and some of the forth files are very long.
 172  */
 173 struct includeline
 174 {
 175     struct includeline  *next;
 176     int                 line;
 177     char                text[0];
 178 };
 179
 180 /*
 181  * The PXE TFTP service allows opening exactly one connection at the time,
 182  * so we need to read included file into memory, then process line by line
 183  * as it may contain embedded include commands.
 184  */
 185 int
 186 include(const char *filename)
 187 {
 188     struct includeline  *script, *se, *sp;
 189     int res = CMD_OK;
 190     int prevsrcid, fd, line;
 191     char *cp, input[256];               /* big enough? */
 192
 193     if (((fd = open(filename, O_RDONLY)) == -1)) {
 194         snprintf(command_errbuf, sizeof (command_errbuf), "can't open '%s': %s",
 195             filename, strerror(errno));
 196         return(CMD_ERROR);
 197     }
 198     /*
 199      * Read the script into memory.
 200      */
 201     script = se = NULL;
 202     line = 0;
 203
 204     while (fgetstr(input, sizeof(input), fd) >= 0) {
 205         line++;
 206         cp = input;
 207         /* Allocate script line structure and copy line, flags */
 208         if (*cp == '\0')
 209                 continue;       /* ignore empty line, save memory */
 210         if (cp[0] == '\\' && cp[1] == ' ')
 211                 continue;       /* ignore comment */
 212
 213         sp = malloc(sizeof(struct includeline) + strlen(cp) + 1);
 214         /* On malloc failure (it happens!), free as much as possible and exit */
 215         if (sp == NULL) {
 216                 while (script != NULL) {
 217                         se = script;
 218                         script = script->next;
 219                         free(se);
 220                 }
 221                 snprintf(command_errbuf, sizeof (command_errbuf),
 222                     "file '%s' line %d: memory allocation failure - aborting",
 223                     filename, line);
 224                 close(fd);
 225                 return (CMD_ERROR);
 226         }
 227         strcpy(sp->text, cp);
 228         sp->line = line;
 229         sp->next = NULL;
 230
 231         if (script == NULL) {
 232                 script = sp;
 233         } else {
 234                 se->next = sp;
 235         }
 236         se = sp;
 237     }
 238     close(fd);
 239
 240     /*
 241      * Execute the script
 242      */
 243
 244     prevsrcid = bf_vm->sourceId.i;
 245     bf_vm->sourceId.i = fd+1;   /* 0 is user input device */
 246
 247     res = CMD_OK;
 248
 249     for (sp = script; sp != NULL; sp = sp->next) {
 250         res = bf_run(sp->text);
 251         if (res != FICL_VM_STATUS_OUT_OF_TEXT) {
 252                 snprintf(command_errbuf, sizeof (command_errbuf),
 253                     "Error while including %s, in the line %d:\n%s",
 254                     filename, sp->line, sp->text);
 255                 res = CMD_ERROR;
 256                 break;
 257         } else
 258                 res = CMD_OK;
 259     }
 260
 261     bf_vm->sourceId.i = -1;
 262     (void) bf_run("");
 263     bf_vm->sourceId.i = prevsrcid;
 264
 265     while(script != NULL) {
 266         se = script;
 267         script = script->next;
 268         free(se);
 269     }
 270
 271     return(res);
 272 }
 273
 274 /*
 275  * Emit the current prompt; use the same syntax as the parser
 276  * for embedding environment variables.
 277  */
 278 static char *
 279 prompt(void)
 280 {
 281     static char promptbuf[20];  /* probably too large, but well... */
 282     char        *pr, *p, *cp, *ev;
 283     int n = 0;
 284
 285     if ((cp = getenv("prompt")) == NULL)
 286         cp = (char *)(uintptr_t)">";
 287     pr = p = strdup(cp);
 288
 289     while (*p != 0) {
 290         if ((*p == '$') && (*(p+1) == '{')) {
 291             for (cp = p + 2; (*cp != 0) && (*cp != '}'); cp++)
 292                 ;
 293             *cp = 0;
 294             ev = getenv(p + 2);
 295
 296             if (ev != NULL)
 297                 n = sprintf(promptbuf+n, "%s", ev);
 298             p = cp + 1;
 299             continue;
 300         }
 301         promptbuf[n++] = *p;
 302         p++;
 303     }
 304     if (promptbuf[n - 1] != ' ')
 305         promptbuf[n++] = ' ';
 306     promptbuf[n] = '\0';
 307     free(pr);
 308     return (promptbuf);
 309 }