diff options
Diffstat (limited to 'variables.c')
| -rw-r--r-- | variables.c | 79 |
1 files changed, 60 insertions, 19 deletions
diff --git a/variables.c b/variables.c index 638d6ecd..610629ab 100644 --- a/variables.c +++ b/variables.c @@ -169,6 +169,7 @@ SHELL_VAR nameref_invalid_value; static SHELL_VAR nameref_maxloop_value; static HASH_TABLE *last_table_searched; /* hash_lookup sets this */ +static VAR_CONTEXT *last_context_searched; /* Some forward declarations. */ static void create_variable_tables __P((void)); @@ -1311,34 +1312,48 @@ init_seconds_var () } /* The random number seed. You can change this by setting RANDOM. */ -static unsigned long rseed = 1; +static u_bits32_t rseed = 1; static int last_random_value; static int seeded_subshell = 0; -/* A linear congruential random number generator based on the example - one in the ANSI C standard. This one isn't very good, but a more - complicated one is overkill. */ +#define BASH_RANDOM_16 1 + +#if BASH_RANDOM_16 +# define BASH_RAND_MAX 32767 /* 0x7fff - 16 bits */ +#else +# define BASH_RAND_MAX 0x7fffffff /* 32 bits */ +#endif /* Returns a pseudo-random number between 0 and 32767. */ static int brand () { - /* From "Random number generators: good ones are hard to find", + /* Minimal Standard generator from + "Random number generators: good ones are hard to find", Park and Miller, Communications of the ACM, vol. 31, no. 10, - October 1988, p. 1195. filtered through FreeBSD */ - long h, l; + October 1988, p. 1195. filtered through FreeBSD. + + x(n+1) = 16807 * x(n) mod (2**31 - 1). + + We split up the calculations to avoid overflow. + + h = rseed / q; l = x - h * q; t = a * l - h * r + m = 2147483647, a = 16807, q = 127773, r = 2836 + + There are lots of other combinations of constants to use; look at + https://www.gnu.org/software/gsl/manual/html_node/Other-random-number-generators.html#Other-random-number-generators */ + + bits32_t h, l, t; /* Can't seed with 0. */ if (rseed == 0) rseed = 123459876; h = rseed / 127773; - l = rseed % 127773; - rseed = 16807 * l - 2836 * h; -#if 0 - if (rseed < 0) - rseed += 0x7fffffff; -#endif - return ((unsigned int)(rseed & 32767)); /* was % 32768 */ + l = rseed - (127773 * h); + t = 16807 * l - 2836 * h; + rseed = (t < 0) ? t + 0x7fffffff : t; + + return ((unsigned int)(rseed & BASH_RAND_MAX)); /* was % BASH_RAND_MAX+1 */ } /* Set the random number generator seed to SEED. */ @@ -1354,9 +1369,15 @@ static void seedrand () { struct timeval tv; + SHELL_VAR *v; gettimeofday (&tv, NULL); +#if 0 + v = find_variable ("BASH_VERSION"); + sbrand (tv.tv_sec ^ tv.tv_usec ^ getpid () ^ ((u_bits32_t)&v & 0x7fffffff)); +#else sbrand (tv.tv_sec ^ tv.tv_usec ^ getpid ()); +#endif } static SHELL_VAR * @@ -2607,6 +2628,17 @@ make_local_variable (name, flags) if (was_tmpvar && old_var->context == variable_context && last_table_searched != temporary_env) { VUNSETATTR (old_var, att_invisible); /* XXX */ +#if 0 /* TAG:bash-5.1 */ + /* We still want to flag this variable as local, though, and set things + up so that it gets treated as a local variable. */ + new_var = old_var; + /* Since we found the variable in a temporary environment, this will + succeed. */ + for (vc = shell_variables; vc; vc = vc->down) + if (vc_isfuncenv (vc) && vc->scope == variable_context) + break; + goto set_local_var_flags; +#endif return (old_var); } @@ -2694,6 +2726,7 @@ make_local_variable (name, flags) new_var->attributes = exported_p (old_var) ? att_exported : 0; } +set_local_var_flags: vc->flags |= VC_HASLOCAL; new_var->context = variable_context; @@ -3213,6 +3246,9 @@ bind_variable (name, value, flags) nvc = vc; if (v && nameref_p (v)) { + /* This starts at the context where we found the nameref. If we + want to start the name resolution over again at the original + context, this is where we need to change it */ nv = find_variable_nameref_context (v, vc, &nvc); if (nv == 0) { @@ -3234,8 +3270,9 @@ bind_variable (name, value, flags) else if (nv == &nameref_maxloop_value) { internal_warning (_("%s: circular name reference"), v->name); -#if 0 - return (bind_variable_value (v, value, flags|ASS_NAMEREF)); +#if 1 + /* TAG:bash-5.1 */ + return (bind_global_variable (v->name, value, flags)); #else v = 0; /* backwards compat */ #endif @@ -3246,8 +3283,9 @@ bind_variable (name, value, flags) else if (nv == &nameref_maxloop_value) { internal_warning (_("%s: circular name reference"), v->name); -#if 0 - return (bind_variable_value (v, value, flags|ASS_NAMEREF)); +#if 1 + /* TAG:bash-5.1 */ + return (bind_global_variable (v->name, value, flags)); #else v = 0; /* backwards compat */ #endif @@ -3557,7 +3595,10 @@ assign_in_env (word, flags) but the variable does not already exist, assign to the nameref target and add the target to the temporary environment. This is what ksh93 does */ - if (var && nameref_p (var) && valid_nameref_value (nameref_cell (var), 1)) + /* We use 2 in the call to valid_nameref_value because we don't want + to allow array references here at all (newname will be used to + create a variable directly below) */ + if (var && nameref_p (var) && valid_nameref_value (nameref_cell (var), 2)) { newname = nameref_cell (var); var = 0; /* don't use it for append */ |