diff options
| -rw-r--r-- | shell/ash.c | 68 |
1 files changed, 54 insertions, 14 deletions
diff --git a/shell/ash.c b/shell/ash.c index eb8706f36..8c2493ece 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -37,6 +37,8 @@ * used in busybox and size optimizations, * support locale, rewrited arith (see notes to this) * + * Modified by Paul Mundt <lethal@linux-sh.org> (c) 2004 to support + * dynamic variables. */ @@ -88,7 +90,7 @@ #include <signal.h> #include <stdint.h> #include <sysexits.h> - +#include <time.h> #include <fnmatch.h> @@ -1465,6 +1467,7 @@ static void reset(void); #define VNOFUNC 0x40 /* don't call the callback function */ #define VNOSET 0x80 /* do not set variable - just readonly test */ #define VNOSAVE 0x100 /* when text is on the heap before setvareq */ +#define VDYNAMIC 0x200 /* dynamic variable */ struct var { @@ -1474,6 +1477,9 @@ struct var { void (*func)(const char *); /* function to be called when */ /* the variable gets set/unset */ + char *(*lookup_func)(const char *); + /* function to be called when */ + /* the variable is read (if dynamic) */ }; struct localvar { @@ -1500,6 +1506,9 @@ static void change_lc_all(const char *value); static void change_lc_ctype(const char *value); #endif +static char *get_random(const char *); +static void change_random(const char *); + #define VTABSIZE 39 static const char defpathvar[] = "PATH=/usr/local/bin:/usr/bin:/sbin:/bin"; @@ -1513,30 +1522,32 @@ static const char defifs[] = " \t\n"; static struct var varinit[] = { #ifdef IFS_BROKEN - { 0, VSTRFIXED|VTEXTFIXED, defifsvar, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, defifsvar, 0, 0 }, #else - { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "IFS\0", 0 }, + { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "IFS\0", 0, 0 }, #endif #ifdef CONFIG_ASH_MAIL - { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL\0", changemail }, - { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH\0", changemail }, + { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL\0", changemail, 0 }, + { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH\0", changemail, 0 }, #endif - { 0, VSTRFIXED|VTEXTFIXED, defpathvar, changepath }, - { 0, VSTRFIXED|VTEXTFIXED, "PS1=$ ", 0 }, - { 0, VSTRFIXED|VTEXTFIXED, "PS2=> ", 0 }, - { 0, VSTRFIXED|VTEXTFIXED, "PS4=+ ", 0 }, + { 0, VSTRFIXED|VTEXTFIXED, defpathvar, changepath, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, "PS1=$ ", 0, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, "PS2=> ", 0, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, "PS4=+ ", 0, 0 }, #ifdef CONFIG_ASH_GETOPTS - { 0, VSTRFIXED|VTEXTFIXED, "OPTIND=1", getoptsreset }, + { 0, VSTRFIXED|VTEXTFIXED, "OPTIND=1", getoptsreset, 0 }, #endif #ifdef CONFIG_LOCALE_SUPPORT - {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_ALL=", change_lc_all}, - {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_CTYPE=", change_lc_ctype}, + {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_ALL=", change_lc_all, 0}, + {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_CTYPE=", change_lc_ctype, 0}, #endif #ifdef CONFIG_FEATURE_COMMAND_SAVEHISTORY - {0, VSTRFIXED | VTEXTFIXED | VUNSET, "HISTFILE=", NULL}, + {0, VSTRFIXED | VTEXTFIXED | VUNSET, "HISTFILE=", NULL, 0}, #endif + {0, VSTRFIXED | VTEXTFIXED | VUNSET | VDYNAMIC, "RANDOM\0", + change_random, get_random}, }; #define vifs varinit[0] @@ -9019,6 +9030,22 @@ static void change_lc_ctype(const char *value) #endif +/* Roughly copied from bash.. */ +static unsigned long rseed = 1; +static char *get_random(const char *var) +{ + char buf[255]; + rseed = (rseed + getpid() + ((time_t)time((time_t *)0))); + rseed = rseed * 1103515245 + 12345; + sprintf(buf, "%d", (unsigned int)((rseed >> 16 & 32767))); + return bb_xstrdup(buf); +} + +static void change_random(const char *value) +{ + rseed = strtoul(value, (char **)NULL, 10); +} + #ifdef CONFIG_ASH_GETOPTS static int getopts(char *optstr, char *optvar, char **optfirst, int *param_optind, int *optoff) @@ -12031,9 +12058,20 @@ lookupvar(const char *name) { struct var *v; - if ((v = *findvar(hashvar(name), name)) && !(v->flags & VUNSET)) { + if ((v = *findvar(hashvar(name), name)) && !(v->flags & (VUNSET|VDYNAMIC))) { return strchrnul(v->text, '=') + 1; } + + /* + * Dynamic variables are implemented roughly the same way they are + * in bash. Namely, they're "special" so long as they aren't unset. + * As soon as they're unset, they're no longer dynamic, and dynamic + * lookup will no longer happen at that point. -- PFM. + */ + if (v && ((v->flags & VDYNAMIC))) + if (v->lookup_func) + return v->lookup_func(name); + return NULL; } @@ -12308,6 +12346,8 @@ unsetvar(const char *s) retval = 1; if (flags & VREADONLY) goto out; + if (flags & VDYNAMIC) + vp->flags &= ~VDYNAMIC; if (flags & VUNSET) goto ok; if ((flags & VSTRFIXED) == 0) { |