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Upstream commit: Date: Thu, 27 Dec 2007 13:54:16 +1100 [PARSER] Add FAKEEOFMARK for expandstr Previously expandstr used the string "" to indicate that it needs to be treated just like a here-doc except that there is no terminator. However, the string "" is in fact a valid here-doc terminator so now that we deal with it correctly expandstr no longer works in the presence of new-lines in the prompt. This patch introduces the FAKEEOFMARK macro which does not equal any real EOF marker but is distinct from the NULL pointer which is used to indicate non-here-doc contexts. Thanks to Markus Triska for reporting this regression. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Unfortunately, I did not find the failing example for this old fix. I also tweaked the code which was added by this commit: " Date: Mon Sep 24 18:30:02 2007 +0000 ash: fix prompt expansion (Natanael Copa <natanael.copa@gmail.com>) " since other parts of code do expect expandstr() to use DQSYNTAX, not PSSYNTAX. function old new delta parse_stream 2609 2634 +25 setprompt_if 128 133 +5 read_profile 32 37 +5 evalcommand 1334 1339 +5 expandstr 122 120 -2 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 4/1 up/down: 40/-2) Total: 38 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> |
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.. | ||
ash_test | ||
hush_test | ||
ash_doc.txt | ||
ash_ptr_hack.c | ||
ash.c | ||
brace.txt | ||
Config.src | ||
cttyhack.c | ||
hush_doc.txt | ||
hush_leaktool.sh | ||
hush.c | ||
Kbuild.src | ||
match.c | ||
match.h | ||
math.c | ||
math.h | ||
random.c | ||
random.h | ||
README | ||
README.job | ||
shell_common.c | ||
shell_common.h |
http://www.opengroup.org/onlinepubs/9699919799/ Open Group Base Specifications Issue 7 http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap01.html Shell & Utilities It says that any of the standard utilities may be implemented as a regular shell built-in. It gives a list of utilities which are usually implemented that way (and some of them can only be implemented as built-ins, like "alias"): alias bg cd command false fc fg getopts jobs kill newgrp pwd read true umask unalias wait http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html Shell Command Language It says that shell must implement special built-ins. Special built-ins differ from regular ones by the fact that variable assignments done on special builtin are *PRESERVED*. That is, VAR=VAL special_builtin; echo $VAR should print VAL. (Another distinction is that an error in special built-in should abort the shell, but this is not such a critical difference, and moreover, at least bash's "set" does not follow this rule, which is even codified in autoconf configure logic now...) List of special builtins: . file : [argument...] break [n] continue [n] eval [argument...] exec [command [argument...]] exit [n] export name[=word]... export -p readonly name[=word]... readonly -p return [n] set [-abCefhmnuvx] [-o option] [argument...] set [+abCefhmnuvx] [+o option] [argument...] set -- [argument...] set -o set +o shift [n] times trap n [condition...] trap [action condition...] unset [-fv] name... In practice, no one uses this obscure feature - none of these builtins gives any special reasons to play such dirty tricks. However. This section also says that *function invocation* should act similar to special built-in. That is, variable assignments done on function invocation should be preserved after function invocation. This is significant: it is not unthinkable to want to run a function with some variables set to special values. But because of the above, it does not work: variable will "leak" out of the function.