From 16767e2377210fb7489ee4d7d79ad1850c7c932d Mon Sep 17 00:00:00 2001 From: Eric Andersen Date: Tue, 16 Mar 2004 05:14:10 +0000 Subject: [PATCH] Patch from vodz to fix the dynamic vars patch, which I should not have checked in. Vladimir writes: Your patch have many problem. 1. You always added + time(). This cannot reset RANDOM=value for debuging with replay sequential. 2. Hmm. I examine bash 2.04 source. This pseudorandom generator use low bits of counter value. You use high bits. This make bad pseudorandom values after have 0-value. For example, if + time() do remove, your generator always return 0 after first generate 0. 3. Memory leak per call. Use ash-unlike unecessary bb_strdup function. 4. Unsupport show last $RANDOM value for "set" and "export" command. 5. Bloat code. Busybox-unlike patch - added unstandart feature as default hardcode. Last patch attached. Erik, why you apply Paul patch with have 5-th point problem? :( Last patch have ash change xwrite() to fresh libbb/bb_full_write interfase (haved loop after EINTR). --w vodz --- shell/Config.in | 11 ++++ shell/ash.c | 161 ++++++++++++++++++++++++++---------------------- 2 files changed, 97 insertions(+), 75 deletions(-) diff --git a/shell/Config.in b/shell/Config.in index bcb5e719b..34baaa45c 100644 --- a/shell/Config.in +++ b/shell/Config.in @@ -97,6 +97,17 @@ config CONFIG_ASH_OPTIMIZE_FOR_SIZE help Compile ash for reduced size at price of speed. +config CONFIG_ASH_RANDOM_SUPPORT + bool " Enable pseudorandom generator and variable $RANDOM" + default n + depends on CONFIG_ASH + help + Enable pseudorandom generator and dynamic variable "$RANDOM". + Each read of "$RANDOM" will generate a new pseudorandom value. + You can reset the generator by using a specified start value. + After "unset RANDOM" then generator will switch off and this + variable will no longer have special treatment. + config CONFIG_HUSH bool "hush" default n diff --git a/shell/ash.c b/shell/ash.c index 060860c07..5072528f4 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -33,12 +33,14 @@ * rewrite arith.y to micro stack based cryptic algorithm by * Copyright (c) 2001 Aaron Lehmann * - * Modified by Vladimir Oleynik (c) 2001-2003 to be - * used in busybox and size optimizations, - * support locale, rewrited arith (see notes to this) - * * Modified by Paul Mundt (c) 2004 to support * dynamic variables. + * + * Modified by Vladimir Oleynik (c) 2001-2004 to be + * used in busybox and size optimizations, + * rewrote arith (see notes to this), added locale support, + * rewrote dynamic variables. + * */ @@ -1447,6 +1449,14 @@ static void unsetfunc(const char *); static int dash_arith(const char *); #endif +#ifdef CONFIG_ASH_RANDOM_SUPPORT +static unsigned long rseed; +static void change_random(const char *); +# ifndef DYNAMIC_VAR +# define DYNAMIC_VAR +# endif +#endif + /* $NetBSD: init.h,v 1.9 2002/11/24 22:35:40 christos Exp $ */ static void reset(void); @@ -1467,19 +1477,18 @@ 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 */ - +#ifdef DYNAMIC_VAR +# define VDYNAMIC 0x200 /* dynamic variable */ +# else +# define VDYNAMIC 0 +#endif struct var { struct var *next; /* next entry in hash list */ int flags; /* flags are defined above */ const char *text; /* name=value */ - void (*func)(const char *); - /* function to be called when */ + 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 { @@ -1506,8 +1515,6 @@ 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 @@ -1522,32 +1529,33 @@ static const char defifs[] = " \t\n"; static struct var varinit[] = { #ifdef IFS_BROKEN - { 0, VSTRFIXED|VTEXTFIXED, defifsvar, 0, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, defifsvar, 0 }, #else - { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "IFS\0", 0, 0 }, + { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "IFS\0", 0 }, #endif #ifdef CONFIG_ASH_MAIL - { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL\0", changemail, 0 }, - { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH\0", changemail, 0 }, + { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL\0", changemail }, + { 0, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH\0", changemail }, #endif - { 0, VSTRFIXED|VTEXTFIXED, defpathvar, changepath, 0 }, - { 0, VSTRFIXED|VTEXTFIXED, "PS1=$ ", 0, 0 }, - { 0, VSTRFIXED|VTEXTFIXED, "PS2=> ", 0, 0 }, - { 0, VSTRFIXED|VTEXTFIXED, "PS4=+ ", 0, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, defpathvar, changepath }, + { 0, VSTRFIXED|VTEXTFIXED, "PS1=$ ", 0 }, + { 0, VSTRFIXED|VTEXTFIXED, "PS2=> ", 0 }, + { 0, VSTRFIXED|VTEXTFIXED, "PS4=+ ", 0 }, #ifdef CONFIG_ASH_GETOPTS - { 0, VSTRFIXED|VTEXTFIXED, "OPTIND=1", getoptsreset, 0 }, + { 0, VSTRFIXED|VTEXTFIXED, "OPTIND=1", getoptsreset }, +#endif +#ifdef CONFIG_ASH_RANDOM_SUPPORT + {0, VSTRFIXED|VTEXTFIXED|VUNSET|VDYNAMIC, "RANDOM\0", change_random }, #endif #ifdef CONFIG_LOCALE_SUPPORT - {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_ALL=", change_lc_all, 0}, - {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_CTYPE=", change_lc_ctype, 0}, + {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_ALL\0", change_lc_all }, + {0, VSTRFIXED | VTEXTFIXED | VUNSET, "LC_CTYPE\0", change_lc_ctype }, #endif #ifdef CONFIG_FEATURE_COMMAND_SAVEHISTORY - {0, VSTRFIXED | VTEXTFIXED | VUNSET, "HISTFILE=", NULL, 0}, + {0, VSTRFIXED | VTEXTFIXED | VUNSET, "HISTFILE\0", NULL }, #endif - {0, VSTRFIXED | VTEXTFIXED | VUNSET | VDYNAMIC, "RANDOM\0", - change_random, get_random}, }; #define vifs varinit[0] @@ -1562,7 +1570,11 @@ static struct var varinit[] = { #define vps2 (&vps1)[1] #define vps4 (&vps2)[1] #define voptind (&vps4)[1] - +#ifdef CONFIG_ASH_GETOPTS +#define vrandom (&voptind)[1] +#else +#define vrandom (&vps4)[1] +#endif #define defpath (defpathvar + 5) /* @@ -1630,12 +1642,11 @@ extern char **environ; static void outstr(const char *, FILE *); static void outcslow(int, FILE *); static void flushall(void); -static void flushout(FILE *); +static void flusherr(void); static int out1fmt(const char *, ...) __attribute__((__format__(__printf__,1,2))); static int fmtstr(char *, size_t, const char *, ...) __attribute__((__format__(__printf__,3,4))); -static void xwrite(int, const void *, size_t); static int preverrout_fd; /* save fd2 before print debug if xflag is set. */ @@ -1648,7 +1659,7 @@ static void out1str(const char *p) static void out2str(const char *p) { outstr(p, stderr); - flushout(stderr); + flusherr(); } /* @@ -3287,7 +3298,7 @@ evalcommand(union node *cmd, int flags) } sp = arglist.list; } - xwrite(preverrout_fd, "\n", 1); + bb_full_write(preverrout_fd, "\n", 1); } cmd_is_exec = 0; @@ -3304,7 +3315,7 @@ evalcommand(union node *cmd, int flags) find_command(argv[0], &cmdentry, cmd_flag, path); if (cmdentry.cmdtype == CMDUNKNOWN) { status = 127; - flushout(stderr); + flusherr(); goto bail; } @@ -4571,7 +4582,7 @@ expandhere(union node *arg, int fd) { herefd = fd; expandarg(arg, (struct arglist *)NULL, 0); - xwrite(fd, stackblock(), expdest - (char *)stackblock()); + bb_full_write(fd, stackblock(), expdest - (char *)stackblock()); } @@ -7905,6 +7916,10 @@ ash_main(int argc, char **argv) trputs("Shell args: "); trargs(argv); #endif rootpid = getpid(); + +#ifdef CONFIG_ASH_RANDOM_SUPPORT + rseed = rootpid + ((time_t)time((time_t *)0)); +#endif rootshell = 1; init(); setstackmark(&smark); @@ -8365,7 +8380,7 @@ growstackstr(void) { size_t len = stackblocksize(); if (herefd >= 0 && len >= 1024) { - xwrite(herefd, stackblock(), len); + bb_full_write(herefd, stackblock(), len); return stackblock(); } growstackblock(); @@ -9030,21 +9045,26 @@ static void change_lc_ctype(const char *value) #endif +#ifdef CONFIG_ASH_RANDOM_SUPPORT /* 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); + if(value == NULL) { + /* "get", generate */ + char buf[16]; + + rseed = rseed * 1103515245 + 12345; + sprintf(buf, "%d", (unsigned int)((rseed & 32767))); + /* set without recursion */ + setvar(vrandom.text, buf, VNOFUNC); + vrandom.flags &= ~VNOFUNC; + } else { + /* set/reset */ + rseed = strtoul(value, (char **)NULL, 10); + } } +#endif + #ifdef CONFIG_ASH_GETOPTS static int @@ -9234,10 +9254,10 @@ flushall(void) } void -flushout(FILE *dest) +flusherr(void) { INTOFF; - fflush(dest); + fflush(stderr); INTON; } @@ -9281,20 +9301,6 @@ fmtstr(char *outbuf, size_t length, const char *fmt, ...) } -/* - * Version of write which resumes after a signal is caught. - */ - -static void -xwrite(int fd, const void *p, size_t n) -{ - ssize_t i; - - do { - i = bb_full_write(fd, p, n); - } while (i < 0 && errno == EINTR); -} - /* $NetBSD: parser.c,v 1.54 2002/11/24 22:35:42 christos Exp $ */ @@ -10951,7 +10957,7 @@ openhere(union node *redir) if (redir->type == NHERE) { len = strlen(redir->nhere.doc->narg.text); if (len <= PIPESIZE) { - xwrite(pip[1], redir->nhere.doc->narg.text, len); + bb_full_write(pip[1], redir->nhere.doc->narg.text, len); goto out; } } @@ -10965,7 +10971,7 @@ openhere(union node *redir) #endif signal(SIGPIPE, SIG_DFL); if (redir->type == NHERE) - xwrite(pip[1], redir->nhere.doc->narg.text, len); + bb_full_write(pip[1], redir->nhere.doc->narg.text, len); else expandhere(redir->nhere.doc, pip[1]); _exit(0); @@ -11998,10 +12004,13 @@ setvareq(char *s, int flags) flags |= (VEXPORT & (((unsigned) (1 - aflag)) - 1)); vp = *findvar(vpp, s); if (vp) { - if (vp->flags & VREADONLY) { + if ((vp->flags & (VREADONLY|VDYNAMIC)) == VREADONLY) { + const char *n; + if (flags & VNOSAVE) free(s); - error("%.*s: is read only", strchrnul(s, '=') - s, s); + n = vp->text; + error("%.*s: is read only", strchrnul(n, '=') - n, n); } if (flags & VNOSET) @@ -12058,19 +12067,20 @@ lookupvar(const char *name) { struct var *v; - if ((v = *findvar(hashvar(name), name)) && !(v->flags & (VUNSET|VDYNAMIC))) { - return strchrnul(v->text, '=') + 1; - } - + if ((v = *findvar(hashvar(name), name))) { +#ifdef DYNAMIC_VAR /* * 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); + if((v->flags & VDYNAMIC)) + (*v->func)(NULL); +#endif + if(!(v->flags & VUNSET)) + return strchrnul(v->text, '=') + 1; + } return NULL; } @@ -12346,8 +12356,9 @@ unsetvar(const char *s) retval = 1; if (flags & VREADONLY) goto out; - if (flags & VDYNAMIC) - vp->flags &= ~VDYNAMIC; +#ifdef DYNAMIC_VAR + vp->flags &= ~VDYNAMIC; +#endif if (flags & VUNSET) goto ok; if ((flags & VSTRFIXED) == 0) { -- 2.25.1