diff options
Diffstat (limited to 'shell/ash.c')
-rw-r--r-- | shell/ash.c | 111 |
1 files changed, 73 insertions, 38 deletions
diff --git a/shell/ash.c b/shell/ash.c index 10eb90d30..4f9caa434 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -42,19 +42,18 @@ * a quit signal will generate a core dump. */ #define DEBUG 0 -#define IFS_BROKEN #define PROFILE 0 -#if ENABLE_ASH_JOB_CONTROL -#define JOBS 1 -#else -#define JOBS 0 -#endif + +#define IFS_BROKEN + +#define JOBS ENABLE_ASH_JOB_CONTROL #if DEBUG #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif #endif + #include "busybox.h" /* for applet_names */ #include <paths.h> #include <setjmp.h> @@ -5501,15 +5500,19 @@ expari(int quotes) #endif /* argstr needs it */ -static char *evalvar(char *p, int flag); +static char *evalvar(char *p, int flag, struct strlist *var_str_list); /* * Perform variable and command substitution. If EXP_FULL is set, output CTLESC * characters to allow for further processing. Otherwise treat * $@ like $* since no splitting will be performed. + * + * var_str_list (can be NULL) is a list of "VAR=val" strings which take precedence + * over shell varables. Needed for "A=a B=$A; echo $B" case - we use it + * for correct expansion of "B=$A" word. */ static void -argstr(char *p, int flag) +argstr(char *p, int flag, struct strlist *var_str_list) { static const char spclchars[] ALIGN1 = { '=', @@ -5611,7 +5614,7 @@ argstr(char *p, int flag) p[5] == CTLQUOTEMARK )) ) { - p = evalvar(p + 1, flag) + 1; + p = evalvar(p + 1, flag, /* var_str_list: */ NULL) + 1; goto start; } inquotes = !inquotes; @@ -5627,7 +5630,7 @@ argstr(char *p, int flag) length++; goto addquote; case CTLVAR: - p = evalvar(p, flag); + p = evalvar(p, flag, var_str_list); goto start; case CTLBACKQ: c = 0; @@ -5731,7 +5734,8 @@ varunset(const char *end, const char *var, const char *umsg, int varflags) } static const char * -subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varflags, int quotes) +subevalvar(char *p, char *str, int strloc, int subtype, + int startloc, int varflags, int quotes, struct strlist *var_str_list) { char *startp; char *loc; @@ -5743,7 +5747,8 @@ subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varfla char *(*scan)(char *, char *, char *, char *, int , int); herefd = -1; - argstr(p, subtype != VSASSIGN && subtype != VSQUESTION ? EXP_CASE : 0); + argstr(p, (subtype != VSASSIGN && subtype != VSQUESTION) ? EXP_CASE : 0, + var_str_list); STPUTC('\0', expdest); herefd = saveherefd; argbackq = saveargbackq; @@ -5802,7 +5807,7 @@ subevalvar(char *p, char *str, int strloc, int subtype, int startloc, int varfla * Add the value of a specialized variable to the stack string. */ static ssize_t -varvalue(char *name, int varflags, int flags) +varvalue(char *name, int varflags, int flags, struct strlist *var_str_list) { int num; char *p; @@ -5899,6 +5904,30 @@ varvalue(char *name, int varflags, int flags) p = num ? shellparam.p[num - 1] : arg0; goto value; default: + /* NB: name has form "VAR=..." */ + + /* "A=a B=$A" case: var_str_list is a list of "A=a" strings + * which should be considered before we check variables. */ + if (var_str_list) { + unsigned name_len = (strchrnul(name, '=') - name) + 1; + p = NULL; + do { + char *str = var_str_list->text; + char *eq = strchr(str, '='); + if (!eq) /* stop at first non-assignment */ + break; + eq++; + if (name_len == (eq - str) + && strncmp(str, name, name_len) == 0) { + p = eq; + /* goto value; - WRONG! */ + /* think "A=1 A=2 B=$A" */ + } + var_str_list = var_str_list->next; + } while (var_str_list); + if (p) + goto value; + } p = lookupvar(name); value: if (!p) @@ -5920,20 +5949,17 @@ varvalue(char *name, int varflags, int flags) * input string. */ static char * -evalvar(char *p, int flag) +evalvar(char *p, int flag, struct strlist *var_str_list) { - int subtype; - int varflags; + char varflags; + char subtype; + char quoted; + char easy; char *var; int patloc; - int c; int startloc; ssize_t varlen; - int easy; - int quotes; - int quoted; - quotes = flag & (EXP_FULL | EXP_CASE); varflags = *p++; subtype = varflags & VSTYPE; quoted = varflags & VSQUOTE; @@ -5943,7 +5969,7 @@ evalvar(char *p, int flag) p = strchr(p, '=') + 1; again: - varlen = varvalue(var, varflags, flag); + varlen = varvalue(var, varflags, flag, var_str_list); if (varflags & VSNUL) varlen--; @@ -5957,7 +5983,8 @@ evalvar(char *p, int flag) if (varlen < 0) { argstr( p, flag | EXP_TILDE | - (quoted ? EXP_QWORD : EXP_WORD) + (quoted ? EXP_QWORD : EXP_WORD), + var_str_list ); goto end; } @@ -5968,7 +5995,11 @@ evalvar(char *p, int flag) if (subtype == VSASSIGN || subtype == VSQUESTION) { if (varlen < 0) { - if (subevalvar(p, var, 0, subtype, startloc, varflags, 0)) { + if (subevalvar(p, var, /* strloc: */ 0, + subtype, startloc, varflags, + /* quotes: */ 0, + var_str_list) + ) { varflags &= ~VSNUL; /* * Remove any recorded regions beyond @@ -5993,10 +6024,8 @@ evalvar(char *p, int flag) } if (subtype == VSNORMAL) { - if (!easy) - goto end; - record: - recordregion(startloc, expdest - (char *)stackblock(), quoted); + if (easy) + goto record; goto end; } @@ -6019,8 +6048,11 @@ evalvar(char *p, int flag) */ STPUTC('\0', expdest); patloc = expdest - (char *)stackblock(); - if (subevalvar(p, NULL, patloc, subtype, - startloc, varflags, quotes) == 0) { + if (0 == subevalvar(p, /* str: */ NULL, patloc, subtype, + startloc, varflags, + /* quotes: */ flag & (EXP_FULL | EXP_CASE), + var_str_list) + ) { int amount = expdest - ( (char *)stackblock() + patloc - 1 ); @@ -6028,14 +6060,15 @@ evalvar(char *p, int flag) } /* Remove any recorded regions beyond start of variable */ removerecordregions(startloc); - goto record; + record: + recordregion(startloc, expdest - (char *)stackblock(), quoted); } end: if (subtype != VSNORMAL) { /* skip to end of alternative */ int nesting = 1; for (;;) { - c = *p++; + char c = *p++; if (c == CTLESC) p++; else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) { @@ -6420,7 +6453,8 @@ expandarg(union node *arg, struct arglist *arglist, int flag) STARTSTACKSTR(expdest); ifsfirst.next = NULL; ifslastp = NULL; - argstr(arg->narg.text, flag); + argstr(arg->narg.text, flag, + /* var_str_list: */ arglist ? arglist->list : NULL); p = _STPUTC('\0', expdest); expdest = p - 1; if (arglist == NULL) { @@ -6486,7 +6520,8 @@ casematch(union node *pattern, char *val) argbackq = pattern->narg.backquote; STARTSTACKSTR(expdest); ifslastp = NULL; - argstr(pattern->narg.text, EXP_TILDE | EXP_CASE); + argstr(pattern->narg.text, EXP_TILDE | EXP_CASE, + /* var_str_list: */ NULL); STACKSTRNUL(expdest); result = patmatch(stackblock(), val); popstackmark(&smark); @@ -8249,8 +8284,8 @@ bltincmd(int argc, char **argv) static void evalcommand(union node *cmd, int flags) { - static const struct builtincmd bltin = { - "\0\0", bltincmd + static const struct builtincmd null_bltin = { + "\0\0", bltincmd /* why three NULs? */ }; struct stackmark smark; union node *argp; @@ -8276,7 +8311,7 @@ evalcommand(union node *cmd, int flags) back_exitstatus = 0; cmdentry.cmdtype = CMDBUILTIN; - cmdentry.u.cmd = &bltin; + cmdentry.u.cmd = &null_bltin; varlist.lastp = &varlist.list; *varlist.lastp = NULL; arglist.lastp = &arglist.list; @@ -8352,7 +8387,7 @@ evalcommand(union node *cmd, int flags) } sp = arglist.list; } - full_write(preverrout_fd, "\n", 1); + safe_write(preverrout_fd, "\n", 1); } cmd_is_exec = 0; |