static void xsync_handle(struct xsync_ctx_t * ctx) { uint8_t buf[PACKET_DATA_MAX]; size_t size; switch(ctx->packet.command) { case XSYNC_COMMAND_ALIVE: size = sprintf((char *)buf, "%s", machine_uniqueid()); xsync_put(XSYNC_COMMAND_ALIVE, buf, size); break; case XSYNC_COMMAND_START: buf[0] = xsync_handle_start(ctx); xsync_put(XSYNC_COMMAND_START, buf, 1); break; case XSYNC_COMMAND_TRANSFER: vfs_write(ctx->fd, (void *)ctx->packet.data, packet_dsize(&ctx->packet)); xsync_put(XSYNC_COMMAND_TRANSFER, 0, 0); break; case XSYNC_COMMAND_STOP: if(ctx->fd > 0) { vfs_close(ctx->fd); ctx->fd = -1; } xsync_put(XSYNC_COMMAND_STOP, 0, 0); break; case XSYNC_COMMAND_SYSTEM: xsync_put(XSYNC_COMMAND_SYSTEM, 0, 0); ctx->quit = 1; if(ctx->fd > 0) { vfs_close(ctx->fd); ctx->fd = -1; } memset(buf, 0, sizeof(buf)); memcpy(buf, &ctx->packet.data[0], packet_dsize(&ctx->packet)); shell_system((const char *)buf); break; default: xsync_put(XSYNC_COMMAND_UNKOWN, 0, 0); break; } }
int main(int argc, char *argv[]) { size_t clen, l; int ch, debug, i, magic, n, nargs, rval; char *c, *cmd, *p, *q, *nc; (void)setprogname(argv[0]); /* for portability */ debug = 0; magic = '%'; /* Default magic char is `%'. */ nargs = -1; while ((ch = getopt(argc, argv, "a:d0123456789")) != -1) { switch (ch) { case 'a': if (optarg[1] != '\0') errx(EXIT_FAILURE, "illegal magic character specification."); magic = optarg[0]; break; case 'd': debug = 1; break; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': if (nargs != -1) errx(EXIT_FAILURE, "only one -# argument may be specified."); nargs = optopt - '0'; break; default: usage(); } } argc -= optind; argv += optind; if (argc < 2) usage(); /* * The command to run is argv[0], and the args are argv[1..]. * Look for %digit references in the command, remembering the * largest one. */ for (n = 0, p = argv[0]; *p != '\0'; ++p) { if (p[0] == magic && isdigit((unsigned char)p[1]) && p[1] != '0') { ++p; if (p[0] - '0' > n) n = p[0] - '0'; } } /* * If there were any %digit references, then use those, otherwise * build a new command string with sufficient %digit references at * the end to consume (nargs) arguments each time round the loop. * Allocate enough space to hold the maximum command. */ if ((cmd = malloc(sizeof("exec ") - 1 + strlen(argv[0]) + 9 * (sizeof(" %1") - 1) + 1)) == NULL) err(EXIT_FAILURE, "malloc"); if (n == 0) { /* If nargs not set, default to a single argument. */ if (nargs == -1) nargs = 1; p = cmd; p += sprintf(cmd, "exec %s", argv[0]); for (i = 1; i <= nargs; i++) p += sprintf(p, " %c%d", magic, i); /* * If nargs set to the special value 0, eat a single * argument for each command execution. */ if (nargs == 0) nargs = 1; } else { (void)sprintf(cmd, "exec %s", argv[0]); nargs = n; } /* * Grab some space in which to build the command. Allocate * as necessary later, but no reason to build it up slowly * for the normal case. */ if ((c = malloc(clen = 1024)) == NULL) err(EXIT_FAILURE, "malloc"); /* * (argc) and (argv) are still offset by one to make it simpler to * expand %digit references. At the end of the loop check for (argc) * equals 1 means that all the (argv) has been consumed. */ for (rval = 0; argc > nargs; argc -= nargs, argv += nargs) { /* * Find a max value for the command length, and ensure * there's enough space to build it. */ for (l = strlen(cmd), i = 0; i < nargs; i++) l += strlen(argv[i+1]); if (l > clen) { nc = realloc(c, l); if (nc == NULL) err(EXIT_FAILURE, "malloc"); c = nc; clen = l; } /* Expand command argv references. */ for (p = cmd, q = c; *p != '\0'; ++p) { if (p[0] == magic && isdigit((unsigned char)p[1]) && p[1] != '0') q += sprintf(q, "%s", argv[(++p)[0] - '0']); else *q++ = *p; } /* Terminate the command string. */ *q = '\0'; /* Run the command. */ if (debug) (void)printf("%s\n", c); else if (shell_system(c)) rval = 1; } if (argc != 1) errx(EXIT_FAILURE, "expecting additional argument%s after \"%s\"", (nargs - argc) ? "s" : "", argv[argc - 1]); return rval; }