ash: implement ">&file" bashism. ~100 bytes.

1 files changed, 111 insertions, 47 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 0878237bf..9ccb1c9ee 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -8,7 +8,6 @@
  * Copyright (c) 1997-2005 Herbert Xu <herbert@gondor.apana.org.au>
  * was re-ported from NetBSD and debianized.
  *
- *
  * This code is derived from software contributed to Berkeley by
  * Kenneth Almquist.
  *
@@ -28,7 +27,6 @@
  * used in busybox and size optimizations,
  * rewrote arith (see notes to this), added locale support,
  * rewrote dynamic variables.
- *
  */
 
 /*
@@ -247,8 +245,17 @@ extern struct globals_misc *const ash_ptr_to_globals_misc;
 } while (0)
 
 
-/* ============ Interrupts / exceptions */
+/* ============ Utility functions */
+static int isdigit_str9(const char *str)
+{
+        int maxlen = 9 + 1; /* max 9 digits: 999999999 */
+        while (--maxlen && isdigit(*str))
+                str++;
+        return (*str == '\0');
+}
+
 
+/* ============ Interrupts / exceptions */
 /*
  * These macros allow the user to suspend the handling of interrupt signals
  * over a period of time.  This is similar to SIGHOLD or to sigblock, but
@@ -500,32 +507,35 @@ static const char dolatstr[] ALIGN1 = {
         CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0'
 };
 
-#define NCMD 0
-#define NPIPE 1
-#define NREDIR 2
-#define NBACKGND 3
+#define NCMD      0
+#define NPIPE     1
+#define NREDIR    2
+#define NBACKGND  3
 #define NSUBSHELL 4
-#define NAND 5
-#define NOR 6
-#define NSEMI 7
-#define NIF 8
-#define NWHILE 9
-#define NUNTIL 10
-#define NFOR 11
-#define NCASE 12
-#define NCLIST 13
-#define NDEFUN 14
-#define NARG 15
-#define NTO 16
-#define NCLOBBER 17
-#define NFROM 18
-#define NFROMTO 19
-#define NAPPEND 20
-#define NTOFD 21
-#define NFROMFD 22
-#define NHERE 23
-#define NXHERE 24
-#define NNOT 25
+#define NAND      5
+#define NOR       6
+#define NSEMI     7
+#define NIF       8
+#define NWHILE    9
+#define NUNTIL   10
+#define NFOR     11
+#define NCASE    12
+#define NCLIST   13
+#define NDEFUN   14
+#define NARG     15
+#define NTO      16
+#if ENABLE_ASH_BASH_COMPAT
+#define NTO2     17
+#endif
+#define NCLOBBER 18
+#define NFROM    19
+#define NFROMTO  20
+#define NAPPEND  21
+#define NTOFD    22
+#define NFROMFD  23
+#define NHERE    24
+#define NXHERE   25
+#define NNOT     26
 
 union node;
 
@@ -588,20 +598,26 @@ struct narg {
         struct nodelist *backquote;
 };
 
+/* nfile and ndup layout must match!
+ * NTOFD (>&fdnum) uses ndup structure, but we may discover mid-flight
+ * that it is actually NTO2 (>&file), and change its type.
+ */
 struct nfile {
         smallint type;
         union node *next;
         int fd;
+        int _unused_dupfd;
         union node *fname;
         char *expfname;
 };
 
 struct ndup {
         smallint type;
-        union node *next; /* must match nfile's layout */
-        int fd; /* must match nfile's layout */
+        union node *next;
+        int fd;
         int dupfd;
         union node *vname;
+        char *_unused_expfname;
 };
 
 struct nhere {
@@ -904,8 +920,11 @@ shcmd(union node *cmd, FILE *fp)
                 case NTO:      s = ">>"+1; dftfd = 1; break;
                 case NCLOBBER: s = ">|"; dftfd = 1; break;
                 case NAPPEND:  s = ">>"; dftfd = 1; break;
+#if ENABLE_ASH_BASH_COMPAT
+                case NTO2:
+#endif
                 case NTOFD:    s = ">&"; dftfd = 1; break;
-                case NFROM:    s = "<";  break;
+                case NFROM:    s = "<"; break;
                 case NFROMFD:  s = "<&"; break;
                 case NFROMTO:  s = "<>"; break;
                 default:       s = "*error*"; break;
@@ -4408,6 +4427,9 @@ cmdtxt(union node *n)
         case NAPPEND:
                 p = ">>";
                 goto redir;
+#if ENABLE_ASH_BASH_COMPAT
+        case NTO2:
+#endif
         case NTOFD:
                 p = ">&";
                 goto redir;
@@ -4797,6 +4819,9 @@ openredirect(union node *redir)
                         goto ecreate;
                 break;
         case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+        case NTO2:
+#endif
                 /* Take care of noclobber mode. */
                 if (Cflag) {
                         fname = redir->nfile.expfname;
@@ -4959,6 +4984,10 @@ redirect(union node *redir, int flags)
                 union node *tmp = redir;
                 do {
                         sv_pos++;
+#if ENABLE_ASH_BASH_COMPAT
+                        if (redir->nfile.type == NTO2)
+                                sv_pos++;
+#endif
                         tmp = tmp->nfile.next;
                 } while (tmp);
                 sv = ckmalloc(sizeof(*sv) + sv_pos * sizeof(sv->two_fd[0]));
@@ -4997,6 +5026,9 @@ redirect(union node *redir, int flags)
                                 continue;
                         }
                 }
+#if ENABLE_ASH_BASH_COMPAT
+ redirect_more:
+#endif
                 if (need_to_remember(sv, fd)) {
                         /* Copy old descriptor */
                         i = fcntl(fd, F_DUPFD, 10);
@@ -5039,8 +5071,19 @@ redirect(union node *redir, int flags)
                         }
                 } else if (fd != newfd) { /* move newfd to fd */
                         copyfd(newfd, fd | COPYFD_EXACT);
-                        close(newfd);
+#if ENABLE_ASH_BASH_COMPAT
+                        if (!(redir->nfile.type == NTO2 && fd == 2))
+#endif
+                                close(newfd);
+                }
+#if ENABLE_ASH_BASH_COMPAT
+                if (redir->nfile.type == NTO2 && fd == 1) {
+                        /* We already redirected it to fd 1, now copy it to 2 */
+                        newfd = 1;
+                        fd = 2;
+                        goto redirect_more;
                 }
+#endif
         } while ((redir = redir->nfile.next) != NULL);
 
         INT_ON;
@@ -7641,6 +7684,9 @@ calcsize(union node *n)
                 calcsize(n->narg.next);
                 break;
         case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+        case NTO2:
+#endif
         case NCLOBBER:
         case NFROM:
         case NFROMTO:
@@ -7754,6 +7800,9 @@ copynode(union node *n)
                 new->narg.next = copynode(n->narg.next);
                 break;
         case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+        case NTO2:
+#endif
         case NCLOBBER:
         case NFROM:
         case NFROMTO:
@@ -8175,17 +8224,33 @@ expredir(union node *n)
                 case NFROMTO:
                 case NFROM:
                 case NTO:
+#if ENABLE_ASH_BASH_COMPAT
+                case NTO2:
+#endif
                 case NCLOBBER:
                 case NAPPEND:
                         expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
+#if ENABLE_ASH_BASH_COMPAT
+ store_expfname:
+#endif
                         redir->nfile.expfname = fn.list->text;
                         break;
                 case NFROMFD:
-                case NTOFD:
+                case NTOFD: /* >& */
                         if (redir->ndup.vname) {
                                 expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
                                 if (fn.list == NULL)
                                         ash_msg_and_raise_error("redir error");
+#if ENABLE_ASH_BASH_COMPAT
+//FIXME: we used expandarg with different args!
+                                if (!isdigit_str9(fn.list->text)) {
+                                        /* >&file, not >&fd */
+                                        if (redir->nfile.fd != 1) /* 123>&file - BAD */
+                                                ash_msg_and_raise_error("redir error");
+                                        redir->type = NTO2;
+                                        goto store_expfname;
+                                }
+#endif
                                 fixredir(redir, fn.list->text, 1);
                         }
                         break;
@@ -10126,7 +10191,7 @@ fixredir(union node *n, const char *text, int err)
                 n->ndup.dupfd = -1;
         else {
                 if (err)
-                        raise_error_syntax("Bad fd number");
+                        raise_error_syntax("bad fd number");
                 n->ndup.vname = makename();
         }
 }
@@ -10169,7 +10234,7 @@ parsefname(void)
                         n->type = NXHERE;
                 TRACE(("Here document %d\n", n->type));
                 if (!noexpand(wordtext) || (i = strlen(wordtext)) == 0 || i > EOFMARKLEN)
-                        raise_error_syntax("Illegal eof marker for << redirection");
+                        raise_error_syntax("illegal eof marker for << redirection");
                 rmescapes(wordtext);
                 here->eofmark = wordtext;
                 here->next = NULL;
@@ -10261,7 +10326,7 @@ simplecmd(void)
                                 if (!goodname(name)
                                  || ((bcmd = find_builtin(name)) && IS_BUILTIN_SPECIAL(bcmd))
                                 ) {
-                                        raise_error_syntax("Bad function name");
+                                        raise_error_syntax("bad function name");
                                 }
                                 n->type = NDEFUN;
                                 checkkwd = CHKNL | CHKKWD | CHKALIAS;
@@ -10346,7 +10411,7 @@ parse_command(void)
         }
         case TFOR:
                 if (readtoken() != TWORD || quoteflag || !goodname(wordtext))
-                        raise_error_syntax("Bad for loop variable");
+                        raise_error_syntax("bad for loop variable");
                 n1 = stzalloc(sizeof(struct nfor));
                 n1->type = NFOR;
                 n1->nfor.var = wordtext;
@@ -10748,25 +10813,21 @@ readtoken1(int firstc, int syntax, char *eofmark, int striptabs)
  endword:
 #if ENABLE_ASH_MATH_SUPPORT
         if (syntax == ARISYNTAX)
-                raise_error_syntax("Missing '))'");
+                raise_error_syntax("missing '))'");
 #endif
         if (syntax != BASESYNTAX && !parsebackquote && eofmark == NULL)
-                raise_error_syntax("Unterminated quoted string");
+                raise_error_syntax("unterminated quoted string");
         if (varnest != 0) {
                 startlinno = plinno;
                 /* { */
-                raise_error_syntax("Missing '}'");
+                raise_error_syntax("missing '}'");
         }
         USTPUTC('\0', out);
         len = out - (char *)stackblock();
         out = stackblock();
         if (eofmark == NULL) {
                 if ((c == '>' || c == '<') && quotef == 0) {
-                        int maxlen = 9 + 1; /* max 9 digit fd#: 999999999 */
-                        char *np = out;
-                        while (--maxlen && isdigit(*np))
-                                np++;
-                        if (*np == '\0') {
+                        if (isdigit_str9(out)) {
                                 PARSEREDIR(); /* passed as params: out, c */
                                 lasttoken = TREDIR;
                                 return lasttoken;
@@ -10841,6 +10902,7 @@ parseredir: {
                         np->type = NCLOBBER;
                 else if (c == '&')
                         np->type = NTOFD;
+                        /* it also can be NTO2 (>&file), but we can't figure it out yet */
                 else {
                         np->type = NTO;
                         pungetc();
@@ -10954,8 +11016,10 @@ parsesub: {
                 } else if (is_special(c)) {
                         USTPUTC(c, out);
                         c = pgetc();
-                } else
- badsub:                raise_error_syntax("Bad substitution");
+                } else {
+ badsub:
+                        raise_error_syntax("bad substitution");
+                }
 
                 STPUTC('=', out);
                 flags = 0;