3f4847b6d9
Upstream commit: Date: Sat, 15 Dec 2018 18:49:31 +0100 shell: Fix clang warnings about "string plus integer" Building with clang results in some warnings about integer values being added to strings. While the code itself is fine and the warnings are indeed harmless, fixing them also makes the semantic more explicit: what it is actually being increased is the address which points to the start of the string in order to skip the initial character when some conditions are met. Signed-off-by: Antonio Ospite <ao2@ao2.it> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> 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.