diff options
| -rw-r--r-- | findutils/xargs.c | 52 |
1 files changed, 27 insertions, 25 deletions
diff --git a/findutils/xargs.c b/findutils/xargs.c index 46a62cb..7b9f1fb 100644 --- a/findutils/xargs.c +++ b/findutils/xargs.c @@ -59,14 +59,6 @@ //config: are not special. #include "libbb.h" -/* COMPAT: SYSV version defaults size (and has a max value of) to 470. - We try to make it as large as possible. */ -#if !defined(ARG_MAX) && defined(_SC_ARG_MAX) -# define ARG_MAX sysconf(_SC_ARG_MAX) -#endif -#if !defined(ARG_MAX) -# define ARG_MAX 470 -#endif /* This is a NOEXEC applet. Be very careful! */ @@ -440,35 +432,43 @@ int xargs_main(int argc, char **argv) argc++; } - /* The Open Group Base Specifications Issue 6: + /* -s NUM default. fileutils-4.4.2 uses 128k, but I heasitate + * to use such a big value - first need to change code to use + * growable buffer instead of fixed one. + */ + n_max_chars = 32 * 1024; + /* Make smaller if system does not allow our default value. + * The Open Group Base Specifications Issue 6: * "The xargs utility shall limit the command line length such that * when the command line is invoked, the combined argument * and environment lists (see the exec family of functions * in the System Interfaces volume of IEEE Std 1003.1-2001) * shall not exceed {ARG_MAX}-2048 bytes". */ - n_max_chars = ARG_MAX; /* might be calling sysconf(_SC_ARG_MAX) */ - if (n_max_chars < 4*1024); /* paranoia */ - n_max_chars = 4*1024; - n_max_chars -= 2048; - /* Sanity check for systems with huge ARG_MAX defines (e.g., Suns which - * have it at 1 meg). Things will work fine with a large ARG_MAX - * but it will probably hurt the system more than it needs to; - * an array of this size is allocated. - */ - if (n_max_chars > 20 * 1024) - n_max_chars = 20 * 1024; - + { + long arg_max = 0; +#if defined _SC_ARG_MAX + arg_max = sysconf(_SC_ARG_MAX) - 2048; +#elif defined ARG_MAX + arg_max = ARG_MAX - 2048; +#endif + if (arg_max > 0 && n_max_chars > arg_max) + n_max_chars = arg_max; + } if (opt & OPT_UPTO_SIZE) { - size_t n_chars = 0; n_max_chars = xatou_range(max_chars, 1, INT_MAX); + } + /* Account for prepended fixed arguments */ + { + size_t n_chars = 0; for (i = 0; argv[i]; i++) { n_chars += strlen(argv[i]) + 1; } n_max_chars -= n_chars; - if (n_max_chars <= 0) { - bb_error_msg_and_die("can't fit single argument within argument list size limit"); - } + } + /* Sanity check */ + if (n_max_chars <= 0) { + bb_error_msg_and_die("can't fit single argument within argument list size limit"); } buf = xzalloc(n_max_chars + 1); @@ -476,6 +476,8 @@ int xargs_main(int argc, char **argv) n_max_arg = n_max_chars; if (opt & OPT_UPTO_NUMBER) { n_max_arg = xatou_range(max_args, 1, INT_MAX); + /* Not necessary, we use growable args[]: */ + /* if (n_max_arg > n_max_chars) n_max_arg = n_max_chars */ } /* Allocate pointers for execvp */ |