apps/sh/main.c

   1 /*
   2     meinOS - A unix-like x86 microkernel operating system
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <sys/types.h>
  20 #include <sys/stat.h>
  21 #include <sys/wait.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25 #include <stdio.h>
  26 #include <sys/utsname.h>
  27 #include <pwd.h>
  28 #include <dirent.h>
  29 #include <errno.h>
  30 #include <llist.h>
  31 #include <misc.h>
  32
  33 #include <readline/readline.h>
  34 #include <readline/history.h>
  35
  36 #define TERMINAL_DEVICE "/dev/console"
  37
  38 typedef struct {
  39   const char *cmd;
  40   int (*func)(char **argv);
  41 } shell_builtin_cmd_t;
  42
  43 typedef struct {
  44   pid_t pid;
  45   char *path;
  46   char **argv;
  47   char *stdin;
  48   char *stdout;
  49   char *stderr;
  50 } shell_job_t;
  51
  52 struct utsname utsname;
  53 struct passwd *passwd;
  54 llist_t joblist;
  55
  56 static void usage(char *cmd,int err) {
  57   FILE *out = err?stderr:stdout;
  58   fprintf(out,"Usage: %s\n");
  59   exit(err);
  60 }
  61
  62 /**
  63  * Gets command from shell
  64  *  @return Command line
  65  */
  66 static char *shell_get_command() {
  67   char *cwd = getcwd(NULL,0);
  68   char *prompt;
  69   char *input;
  70
  71   asprintf(&prompt,"%s@%s:%s> ",passwd!=NULL?passwd->pw_name:"nobody",utsname.nodename,cwd);
  72   input = readline(prompt);
  73   if (input!=NULL) {
  74     if (input[0]!=0) add_history(input);
  75   }
  76   else return NULL;
  77
  78   free(prompt);
  79   free(cwd);
  80   return input;
  81 }
  82
  83 /**
  84  * Converts a string with an octal number to an integer
  85  *  @param string String holding octal number
  86  *  @return String as integer
  87  */
  88 static int octal2num(char *str) {
  89   char buf[4];
  90   memcpy(buf,str,3);
  91   buf[3] = 0;
  92   int num = strtoul(buf,NULL,8);
  93   return num;
  94 }
  95
  96 /**
  97  * Parses an command line argument
  98  *  @param arg Command line argument
  99  *  @param len Length of argument
 100  *  @return Parse arguments
 101  */
 102 static char *shell_parse_arg(char *arg,size_t len) {
 103   char *new = malloc(len+1);
 104   size_t i,j;
 105
 106   for (i=0,j=0;i<len;i++,j++) {
 107     if (arg[i]=='\\' && i+1<len) {     // escape code
 108       i++;
 109       if (arg[i]=='\\') new[j] = '\\';      // backslash
 110       else if (arg[i]=='\"') new[j] = '\"'; // quotation mark
 111       else if (arg[i]=='a') new[j] = '\a';  // alert
 112       else if (arg[i]=='b') new[j] = '\b';  // backspace
 113       else if (arg[i]=='f') new[j] = '\f';  // form feed
 114       else if (arg[i]=='n') new[j] = '\n';  // new line
 115       else if (arg[i]=='r') new[j] = '\r';  // carriage return
 116       else if (arg[i]=='t') new[j] = '\t';  // horizontal tab
 117       else if (arg[i]=='v') new[j] = '\v';  // vertical tab
 118       else if (arg[i]=='0' && arg[i+1]!=0 && arg[i+2]!=0 && arg[i+3]!=0) {
 119                                             // character in octal
 120         new[j] = octal2num(arg+i+1);
 121       }
 122     }
 123     else new[j] = arg[i];
 124   }
 125
 126   new[j] = 0;
 127
 128   return new;
 129 }
 130
 131 /**
 132  * Parses a command line string
 133  *  @param cmd Command line string
 134  *  @return Argument vector
 135  */
 136 static char **shell_parse_cmd(char *cmd) {
 137   int quote = 0;
 138   char *cur = cmd;
 139   char *next;
 140   char **argv = NULL;
 141   int argc = 0;
 142
 143   do {
 144     // skip spaces
 145     while (*cur==' ') cur++;
 146     if (*cur==0) break;
 147
 148     // find next space (or quotation mark)
 149     next = strchr(cur,quote?'\"':' ');
 150     if (next==NULL) next = cmd+strlen(cmd);
 151
 152     // if next character is a quotation mark, activate qoutation mode
 153     //if (*next=='\"') qoute = 1;
 154
 155     // add current to argv
 156     argv = realloc(argv,(argc+1)*sizeof(char*));
 157     argv[argc++] = shell_parse_arg(cur,next-cur);
 158     cur = next+1;
 159   } while (*next!=0);
 160
 161   if (argc>0) {
 162     argv = realloc(argv,(argc+1)*sizeof(char*));
 163     argv[argc] = NULL;
 164     return argv;
 165   }
 166   else return NULL;
 167 }
 168
 169 static int shell_builtin_exit(char **argv) {
 170   return 1;
 171 }
 172
 173 static int shell_builtin_help(char **argv) {
 174   printf("Built-in commands:\n"
 175          " exit              Exit shell\n"
 176          " cd DIR            Change working directory to DIR\n"
 177          " ls [DIR]          List content of DIR\n"
 178          " help              Show this help dialog\n"
 179          " version           Show version\n");
 180   return 0;
 181 }
 182
 183 static int shell_builtin_version(char **argv) {
 184   printf("%s %s\n",utsname.sysname,utsname.version);
 185   return 0;
 186 }
 187
 188 static int shell_builtin_cd(char **argv) {
 189   if (argv[1]!=NULL) {
 190     if (chdir(argv[1])==-1) fprintf(stderr,"sh: cd: %s: %s\n",argv[1],strerror(errno));
 191   }
 192   return 0;
 193 }
 194
 195 static char ls_filetype(mode_t mode) {
 196   if (S_ISBLK(mode)) return 'b';
 197   else if (S_ISCHR(mode)) return 'c';
 198   else if (S_ISDIR(mode)) return 'd';
 199   else if (S_ISFIFO(mode)) return 'f';
 200   else if (S_ISLNK(mode)) return 'l';
 201   else if (S_ISSOCK(mode)) return 's';
 202   else return '-';
 203 }
 204
 205 static char *ls_perm(mode_t mode) {
 206   static char buf[10];
 207   snprintf(buf,10,"%c%c%c%c%c%c%c%c%c",mode&S_IRUSR?'r':'-',mode&S_IWUSR?'w':'-',mode&S_IXUSR?'x':'-',mode&S_IRGRP?'r':'-',mode&S_IWGRP?'w':'-',mode&S_IXGRP?'x':'-',mode&S_IROTH?'r':'-',mode&S_IWOTH?'w':'-',mode&S_IXOTH?'x':'-');
 208   return buf;
 209 }
 210
 211 static int shell_builtin_ls(char **argv) {
 212   char *path = argv[1]==NULL?".":argv[1];
 213
 214   DIR *dir = opendir(path);
 215   if (dir!=NULL) {
 216     struct dirent *dirent;
 217     do {
 218       dirent = readdir(dir);
 219       if (dirent!=NULL) {
 220         if (strcmp(dirent->d_name,".")!=0 && strcmp(dirent->d_name,"..")!=0) {
 221           struct stat stbuf;
 222           struct passwd *owner;
 223           char *file;
 224           asprintf(&file,"%s/%s",path,dirent->d_name);
 225           if (stat(file,&stbuf)==-1) printf("Error (%d): %s\n",errno,strerror(errno));
 226           owner = getpwuid(stbuf.st_uid);
 227           printf("%c%s %s % 5d %s\n",ls_filetype(stbuf.st_mode),ls_perm(stbuf.st_mode),owner!=NULL?owner->pw_name:"root",stbuf.st_size,dirent->d_name);
 228         }
 229       }
 230     } while (dirent!=NULL);
 231     return 0;
 232   }
 233   else return 1;
 234 }
 235
 236 int shell_builtin_cat(char **argv) {
 237   FILE *in;
 238
 239   if (argv[1]==NULL) in = stdin;
 240   else {
 241     in = fopen(argv[1],"r");
 242     if (in==NULL) return 1;
 243   }
 244
 245   while (!feof(in)) {
 246     char buf[512];
 247     size_t size = fread(buf,1,512,in);
 248     fwrite(buf,1,size,stdout);
 249   }
 250
 251   return 0;
 252 }
 253
 254 /*int shell_builtin_echo(char **argv) {
 255   size_t i;
 256   for (i=1;argv[i]!=NULL;i++) printf("%s%s",argv[i],argv[i+1]!=NULL?" ":"");
 257   putchar('\n');
 258   return 0;
 259 }*/
 260
 261 int shell_builtin_test(char **argv) {
 262   char buf[32] = {0};
 263   ssize_t n;
 264
 265   printf("Creating FIFO...\n");
 266   mknod("foobar",S_IFIFO|0755,0);
 267
 268   printf("Opening end A (w)...\n");
 269   FILE *enda = fopen("foobar","w");
 270   if (enda==NULL) return 1;
 271
 272   printf("Opening end B (r)...\n");
 273   FILE *endb = fopen("foobar","r");
 274   if (endb==NULL) return 1;
 275
 276   printf("Opening end C (r)...\n");
 277   FILE *endc = fopen("foobar","r");
 278   if (endc==NULL) return 1;
 279
 280   printf("Opening end D (w)...\n");
 281   FILE *endd = fopen("foobar","w");
 282   if (endd==NULL) return 1;
 283
 284   printf("Writing to A...\n");
 285   n = fputs("Hello World\n",enda);
 286   if (n==-1) return 1;
 287   printf("Written %d bytes\n",n);
 288
 289   printf("Reading from B...\n");
 290   if (fgets(buf,32,endb)==NULL) return 1;
 291   printf("\"%s\"\n",buf);
 292
 293   printf("Reading from C...\n");
 294   if (fgets(buf,32,endc)==NULL) return 1;
 295   printf("\"%s\"\n",buf);
 296
 297   printf("Writing to D...\n");
 298   n = fputs("Hallo Welt\n",endd);
 299   if (n==-1) return 1;
 300   printf("Written %d bytes\n",n);
 301
 302   printf("Reading from B...\n");
 303   if (fgets(buf,32,endb)==NULL) return 1;
 304   printf("\"%s\"\n",buf);
 305
 306   printf("Reading from C...\n");
 307   if (fgets(buf,32,endc)==NULL) return 1;
 308   printf("\"%s\"\n",buf);
 309
 310   return 0;
 311 }
 312
 313 /// @todo Sourcecode von utils/echo.c cat.c (und ls.c) hierher und main() in shell_builtin_* umbennen.
 314 static int shell_run_builtin(char **argv) {
 315   shell_builtin_cmd_t shell_builtin_cmds[] = {
 316     { .cmd = "exit",     .func = shell_builtin_exit },
 317     { .cmd = "help",     .func = shell_builtin_help },
 318     { .cmd = "version",  .func = shell_builtin_version },
 319     { .cmd = "cd",       .func = shell_builtin_cd },
 320     { .cmd = "ls",       .func = shell_builtin_ls },
 321     { .cmd = "cat",      .func = shell_builtin_cat },
 322     //{ .cmd = "echo",     .func = shell_builtin_echo },
 323     { .cmd = "test",     .func = shell_builtin_test }
 324   };
 325   size_t i;
 326
 327   for (i=0;i<sizeof(shell_builtin_cmds)/sizeof(shell_builtin_cmd_t);i++) {
 328     if (strcmp(argv[0],shell_builtin_cmds[i].cmd)==0) return shell_builtin_cmds[i].func(argv);
 329   }
 330
 331   return -1;
 332 }
 333
 334 static char *shell_find_path(char *cmd) {
 335   char *path;
 336   /// @todo read from PATH enviroment variable
 337   asprintf(&path,"/boot/bin/%s",cmd);
 338   return path;
 339 }
 340
 341 static int shell_run_binary(char **argv,int background) {
 342   shell_job_t *job = malloc(sizeof(shell_job_t));
 343   job->path = shell_find_path(argv[0]);
 344   job->argv = argv;
 345   job->stdin = TERMINAL_DEVICE;
 346   job->stdout = TERMINAL_DEVICE;
 347   job->stderr = TERMINAL_DEVICE;
 348   job->pid = execute(job->path,argv,job->stdin,job->stdout,job->stderr);
 349
 350   if (job->pid==-1) {
 351     free(job->path);
 352     free(job);
 353     return -1;
 354   }
 355
 356   if (background) {
 357     llist_push(joblist,job);
 358     printf("+[%d]\n",job->pid);
 359   }
 360   else {
 361     int status;
 362     waitpid(job->pid,&status,0);
 363
 364     free(job->path);
 365     free(job);
 366
 367     if (status!=0) fprintf(stderr,"sh: %s: returned with %d\n",argv[0],status);
 368   }
 369
 370   return 0;
 371 }
 372
 373 /**
 374  * Runs shell interactive
 375  */
 376 static void shell_interactive() {
 377   int status = 0;
 378
 379   while (status!=1) {
 380     size_t i;
 381     char **argv;
 382     char *cmd;
 383
 384     if ((cmd = shell_get_command())==NULL) break;
 385
 386     if ((argv = shell_parse_cmd(cmd))!=NULL) {
 387       if ((status = shell_run_builtin(argv))==-1) {
 388         if (shell_run_binary(argv,0)==-1) fprintf(stderr,"sh: %s: command not found\n",argv[0]);
 389       }
 390
 391       for (i=0;argv[i];i++) free(argv[i]);
 392       free(argv);
 393     }
 394
 395     free(cmd);
 396   }
 397 }
 398
 399 int main(int argc,char *argv[]) {
 400   int c;
 401
 402   FILE *terminal = fopen(TERMINAL_DEVICE,"r+");
 403   if (terminal==NULL) return 1;
 404
 405   FILE *stdin_bak = stdin;
 406   FILE *stdout_bak = stdout;
 407   FILE *stderr_bak = stderr;
 408   stdin = terminal;
 409   stdout = terminal;
 410   stderr = terminal;
 411
 412   while ((c = getopt(argc,argv,":hv"))!=-1) {
 413     switch(c) {
 414       case 'h':
 415         usage(argv[0],0);
 416         break;
 417       case 'v':
 418         printf("sh v0.1\n(c) 2008 Janosch Graef\n");
 419         return 0;
 420         break;
 421       case '?':
 422         fprintf(stderr,"Unrecognized option: -%c\n", optopt);
 423         usage(argv[0],1);
 424         break;
 425     }
 426   }
 427
 428   uname(&utsname);
 429   passwd = getpwuid(getuid());
 430   shell_interactive();
 431
 432   stdin = stdin_bak;
 433   stdout = stdout_bak;
 434   stderr = stderr_bak;
 435   fclose(terminal);
 436
 437   return 0;
 438 }