diff options
Diffstat (limited to 'shell/shell_common.c')
-rw-r--r-- | shell/shell_common.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/shell/shell_common.c b/shell/shell_common.c index 669a18dfd..3114ff3f7 100644 --- a/shell/shell_common.c +++ b/shell/shell_common.c @@ -33,3 +33,423 @@ int FAST_FUNC is_well_formed_var_name(const char *s, char terminator) return *s == terminator; } + +/* read builtin */ + +//TODO: use more efficient setvar() which takes a pointer to malloced "VAR=VAL" +//string. hush naturally has it, and ash has setvareq(). +//Here we can simply store "VAR=" at buffer start and store read data directly +//after "=", then pass buffer to setvar() to consume. +const char* FAST_FUNC +shell_builtin_read(void FAST_FUNC (*setvar)(const char *name, const char *val), + char **argv, + const char *ifs, + int read_flags, + const char *opt_n, + const char *opt_p, + const char *opt_t, + const char *opt_u +) +{ + unsigned end_ms; /* -t TIMEOUT */ + int fd; /* -u FD */ + int nchars; /* -n NUM */ + char **pp; + char *buffer; + struct termios tty, old_tty; + const char *retval; + int bufpos; /* need to be able to hold -1 */ + int startword; + smallint backslash; + + pp = argv; + while (*pp) { + if (!is_well_formed_var_name(*pp, '\0')) { + /* Mimic bash message */ + bb_error_msg("read: '%s': not a valid identifier", *pp); + return (const char *)(uintptr_t)1; + } + pp++; + } + + nchars = 0; /* if != 0, -n is in effect */ + if (opt_n) { + nchars = bb_strtou(opt_n, NULL, 10); + if (nchars < 0 || errno) + return "invalid count"; + /* note: "-n 0": off (bash 3.2 does this too) */ + } + end_ms = 0; + if (opt_t) { + end_ms = bb_strtou(opt_t, NULL, 10); + if (errno || end_ms > UINT_MAX / 2048) + return "invalid timeout"; + end_ms *= 1000; +#if 0 /* even bash has no -t N.NNN support */ + ts.tv_sec = bb_strtou(opt_t, &p, 10); + ts.tv_usec = 0; + /* EINVAL means number is ok, but not terminated by NUL */ + if (*p == '.' && errno == EINVAL) { + char *p2; + if (*++p) { + int scale; + ts.tv_usec = bb_strtou(p, &p2, 10); + if (errno) + return "invalid timeout"; + scale = p2 - p; + /* normalize to usec */ + if (scale > 6) + return "invalid timeout"; + while (scale++ < 6) + ts.tv_usec *= 10; + } + } else if (ts.tv_sec < 0 || errno) { + return "invalid timeout"; + } + if (!(ts.tv_sec | ts.tv_usec)) { /* both are 0? */ + return "invalid timeout"; + } +#endif /* if 0 */ + } + fd = STDIN_FILENO; + if (opt_u) { + fd = bb_strtou(opt_u, NULL, 10); + if (fd < 0 || errno) + return "invalid file descriptor"; + } + + if (opt_p && isatty(fd)) { + fputs(opt_p, stderr); + fflush_all(); + } + + if (ifs == NULL) + ifs = defifs; + + if (nchars || (read_flags & BUILTIN_READ_SILENT)) { + tcgetattr(fd, &tty); + old_tty = tty; + if (nchars) { + tty.c_lflag &= ~ICANON; + tty.c_cc[VMIN] = nchars < 256 ? nchars : 255; + } + if (read_flags & BUILTIN_READ_SILENT) { + tty.c_lflag &= ~(ECHO | ECHOK | ECHONL); + } + /* This forces execution of "restoring" tcgetattr later */ + read_flags |= BUILTIN_READ_SILENT; + /* if tcgetattr failed, tcsetattr will fail too. + * Ignoring, it's harmless. */ + tcsetattr(fd, TCSANOW, &tty); + } + + retval = (const char *)(uintptr_t)0; + startword = 1; + backslash = 0; + if (end_ms) /* NB: end_ms stays nonzero: */ + end_ms = ((unsigned)monotonic_ms() + end_ms) | 1; + buffer = NULL; + bufpos = 0; + do { + char c; + + if (end_ms) { + int timeout; + struct pollfd pfd[1]; + + pfd[0].fd = fd; + pfd[0].events = POLLIN; + timeout = end_ms - (unsigned)monotonic_ms(); + if (timeout <= 0 /* already late? */ + || safe_poll(pfd, 1, timeout) != 1 /* no? wait... */ + ) { /* timed out! */ + retval = (const char *)(uintptr_t)1; + goto ret; + } + } + + if ((bufpos & 0xff) == 0) + buffer = xrealloc(buffer, bufpos + 0x100); + if (nonblock_safe_read(fd, &buffer[bufpos], 1) != 1) { + retval = (const char *)(uintptr_t)1; + break; + } + c = buffer[bufpos]; + if (c == '\0') + continue; + if (backslash) { + backslash = 0; + if (c != '\n') + goto put; + continue; + } + if (!(read_flags & BUILTIN_READ_RAW) && c == '\\') { + backslash = 1; + continue; + } + if (c == '\n') + break; + + /* $IFS splitting. NOT done if we run "read" + * without variable names (bash compat). + * Thus, "read" and "read REPLY" are not the same. + */ + if (argv[0]) { +/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_06_05 */ + const char *is_ifs = strchr(ifs, c); + if (startword && is_ifs) { + if (isspace(c)) + continue; + /* it is a non-space ifs char */ + startword--; + if (startword == 1) /* first one? */ + continue; /* yes, it is not next word yet */ + } + startword = 0; + if (argv[1] != NULL && is_ifs) { + buffer[bufpos] = '\0'; + bufpos = 0; + setvar(*argv, buffer); + argv++; + /* can we skip one non-space ifs char? (2: yes) */ + startword = isspace(c) ? 2 : 1; + continue; + } + } + put: + bufpos++; + } while (--nchars); + + if (argv[0]) { + /* Remove trailing space $IFS chars */ + while (--bufpos >= 0 && isspace(buffer[bufpos]) && strchr(ifs, buffer[bufpos]) != NULL) + continue; + buffer[bufpos + 1] = '\0'; + /* Use the remainder as a value for the next variable */ + setvar(*argv, buffer); + /* Set the rest to "" */ + while (*++argv) + setvar(*argv, ""); + } else { + /* Note: no $IFS removal */ + buffer[bufpos] = '\0'; + setvar("REPLY", buffer); + } + + ret: + free(buffer); + if (read_flags & BUILTIN_READ_SILENT) + tcsetattr(fd, TCSANOW, &old_tty); + return retval; +} + +/* ulimit builtin */ + +struct limits { + uint8_t cmd; /* RLIMIT_xxx fit into it */ + uint8_t factor_shift; /* shift by to get rlim_{cur,max} values */ + char option; + const char *name; +}; + +static const struct limits limits_tbl[] = { +#ifdef RLIMIT_FSIZE + { RLIMIT_FSIZE, 9, 'f', "file size (blocks)" }, +#endif +#ifdef RLIMIT_CPU + { RLIMIT_CPU, 0, 't', "cpu time (seconds)" }, +#endif +#ifdef RLIMIT_DATA + { RLIMIT_DATA, 10, 'd', "data seg size (kb)" }, +#endif +#ifdef RLIMIT_STACK + { RLIMIT_STACK, 10, 's', "stack size (kb)" }, +#endif +#ifdef RLIMIT_CORE + { RLIMIT_CORE, 9, 'c', "core file size (blocks)" }, +#endif +#ifdef RLIMIT_RSS + { RLIMIT_RSS, 10, 'm', "resident set size (kb)" }, +#endif +#ifdef RLIMIT_MEMLOCK + { RLIMIT_MEMLOCK, 10, 'l', "locked memory (kb)" }, +#endif +#ifdef RLIMIT_NPROC + { RLIMIT_NPROC, 0, 'p', "processes" }, +#endif +#ifdef RLIMIT_NOFILE + { RLIMIT_NOFILE, 0, 'n', "file descriptors" }, +#endif +#ifdef RLIMIT_AS + { RLIMIT_AS, 10, 'v', "address space (kb)" }, +#endif +#ifdef RLIMIT_LOCKS + { RLIMIT_LOCKS, 0, 'w', "locks" }, +#endif +}; + +enum { + OPT_hard = (1 << 0), + OPT_soft = (1 << 1), +}; + +/* "-": treat args as parameters of option with ASCII code 1 */ +static const char ulimit_opt_string[] = "-HSa" +#ifdef RLIMIT_FSIZE + "f::" +#endif +#ifdef RLIMIT_CPU + "t::" +#endif +#ifdef RLIMIT_DATA + "d::" +#endif +#ifdef RLIMIT_STACK + "s::" +#endif +#ifdef RLIMIT_CORE + "c::" +#endif +#ifdef RLIMIT_RSS + "m::" +#endif +#ifdef RLIMIT_MEMLOCK + "l::" +#endif +#ifdef RLIMIT_NPROC + "p::" +#endif +#ifdef RLIMIT_NOFILE + "n::" +#endif +#ifdef RLIMIT_AS + "v::" +#endif +#ifdef RLIMIT_LOCKS + "w::" +#endif + ; + +static void printlim(unsigned opts, const struct rlimit *limit, + const struct limits *l) +{ + rlim_t val; + + val = limit->rlim_max; + if (!(opts & OPT_hard)) + val = limit->rlim_cur; + + if (val == RLIM_INFINITY) + printf("unlimited\n"); + else { + val >>= l->factor_shift; + printf("%llu\n", (long long) val); + } +} + +int FAST_FUNC +shell_builtin_ulimit(char **argv) +{ + unsigned opts; + unsigned argc; + + /* We can't use getopt32: need to handle commands like + * ulimit 123 -c2 -l 456 + */ + + /* In case getopt was already called: + * reset the libc getopt() function, which keeps internal state. + */ +#ifdef __GLIBC__ + optind = 0; +#else /* BSD style */ + optind = 1; + /* optreset = 1; */ +#endif + /* optarg = NULL; opterr = 0; optopt = 0; - do we need this?? */ + + argc = 1; + while (argv[argc]) + argc++; + + opts = 0; + while (1) { + struct rlimit limit; + const struct limits *l; + int opt_char = getopt(argc, argv, ulimit_opt_string); + + if (opt_char == -1) + break; + if (opt_char == 'H') { + opts |= OPT_hard; + continue; + } + if (opt_char == 'S') { + opts |= OPT_soft; + continue; + } + + if (opt_char == 'a') { + for (l = limits_tbl; l != &limits_tbl[ARRAY_SIZE(limits_tbl)]; l++) { + getrlimit(l->cmd, &limit); + printf("-%c: %-30s ", l->option, l->name); + printlim(opts, &limit, l); + } + continue; + } + + if (opt_char == 1) + opt_char = 'f'; + for (l = limits_tbl; l != &limits_tbl[ARRAY_SIZE(limits_tbl)]; l++) { + if (opt_char == l->option) { + char *val_str; + + getrlimit(l->cmd, &limit); + + val_str = optarg; + if (!val_str && argv[optind] && argv[optind][0] != '-') + val_str = argv[optind++]; /* ++ skips NN in "-c NN" case */ + if (val_str) { + rlim_t val; + + if (strcmp(val_str, "unlimited") == 0) + val = RLIM_INFINITY; + else { + if (sizeof(val) == sizeof(int)) + val = bb_strtou(val_str, NULL, 10); + else if (sizeof(val) == sizeof(long)) + val = bb_strtoul(val_str, NULL, 10); + else + val = bb_strtoull(val_str, NULL, 10); + if (errno) { + bb_error_msg("bad number"); + return EXIT_FAILURE; + } + val <<= l->factor_shift; + } +//bb_error_msg("opt %c val_str:'%s' val:%lld", opt_char, val_str, (long long)val); + if (opts & OPT_hard) + limit.rlim_max = val; + if ((opts & OPT_soft) || opts == 0) + limit.rlim_cur = val; +//bb_error_msg("setrlimit(%d, %lld, %lld)", l->cmd, (long long)limit.rlim_cur, (long long)limit.rlim_max); + if (setrlimit(l->cmd, &limit) < 0) { + bb_perror_msg("error setting limit"); + return EXIT_FAILURE; + } + } else { + printlim(opts, &limit, l); + } + break; + } + } /* for (every possible opt) */ + + if (l == &limits_tbl[ARRAY_SIZE(limits_tbl)]) { + /* bad option. getopt already complained. */ + break; + } + + } /* while (there are options) */ + + return 0; +} |