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author | Paul Eggert <eggert@cs.ucla.edu> | 2018-08-21 13:44:03 -0700 |
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committer | Paul Eggert <eggert@cs.ucla.edu> | 2018-08-21 13:44:32 -0700 |
commit | f18af6cd5cb7dbbf7420ec2d3efed4e202c4f0dd (patch) | |
tree | 5f42e48e12a0ec77bd5cd5f32255a534635e89bf /lisp/net/dns.el | |
parent | 81e7eef8224c8a99a207b7a7b9dae1d598392ef7 (diff) | |
download | emacs-f18af6cd5cb7dbbf7420ec2d3efed4e202c4f0dd.tar.gz emacs-f18af6cd5cb7dbbf7420ec2d3efed4e202c4f0dd.tar.bz2 emacs-f18af6cd5cb7dbbf7420ec2d3efed4e202c4f0dd.zip |
Audit use of lsh and fix glitches
I audited use of lsh in the Lisp source code, and fixed the
glitches that I found. While I was at it, I replaced uses of lsh
with ash when either will do. Replacement is OK when either
argument is known to be nonnegative, or when only the low-order
bits of the result matter, and is a (minor) win since ash is a bit
more solid than lsh nowadays, and is a bit faster.
* lisp/calc/calc-ext.el (math-check-fixnum):
Prefer most-positive-fixnum to (lsh -1 -1).
* lisp/vc/vc-hg.el (vc-hg-state-fast): When testing fixnum width,
prefer (zerop (ash most-positive-fixnum -32)) to (zerop (lsh -1
32)) (Bug#32485#11).
* lisp/emacs-lisp/bytecomp.el (byte-compile-lapcode):
Tighten sanity-check for bytecode overflow, by checking that the
result of (ash pc -8) is nonnegative. Formerly this check was not
needed since lsh was used and the number overflowed differently.
* lisp/net/dns.el (dns-write): Fix some obvious sign typos in
shift counts. Evidently this part of the code has never been
exercised.
* lisp/progmodes/hideif.el (hif-shiftleft, hif-shiftright):
* lisp/term/common-win.el (x-setup-function-keys):
Simplify.
* admin/unidata/unidata-gen.el, admin/unidata/uvs.el:
* doc/lispref/keymaps.texi, doc/lispref/syntax.texi:
* doc/misc/calc.texi, doc/misc/cl.texi, etc/NEWS.19:
* lisp/arc-mode.el, lisp/calc/calc-bin.el, lisp/calc/calc-comb.el:
* lisp/calc/calc-ext.el, lisp/calc/calc-math.el:
* lisp/cedet/semantic/wisent/comp.el, lisp/composite.el:
* lisp/disp-table.el, lisp/dos-fns.el, lisp/edmacro.el:
* lisp/emacs-lisp/bindat.el, lisp/emacs-lisp/byte-opt.el:
* lisp/emacs-lisp/bytecomp.el, lisp/emacs-lisp/cl-extra.el:
* lisp/erc/erc-dcc.el, lisp/facemenu.el, lisp/gnus/message.el:
* lisp/gnus/nndoc.el, lisp/gnus/nnmaildir.el, lisp/image.el:
* lisp/international/ccl.el, lisp/international/fontset.el:
* lisp/international/mule-cmds.el, lisp/international/mule.el:
* lisp/json.el, lisp/mail/binhex.el, lisp/mail/rmail.el:
* lisp/mail/uudecode.el, lisp/md4.el, lisp/net/dns.el:
* lisp/net/ntlm.el, lisp/net/sasl.el, lisp/net/socks.el:
* lisp/net/tramp.el, lisp/obsolete/levents.el:
* lisp/obsolete/pgg-parse.el, lisp/org/org.el:
* lisp/org/ox-publish.el, lisp/progmodes/cc-defs.el:
* lisp/progmodes/ebnf2ps.el, lisp/progmodes/hideif.el:
* lisp/ps-bdf.el, lisp/ps-print.el, lisp/simple.el:
* lisp/tar-mode.el, lisp/term/common-win.el:
* lisp/term/tty-colors.el, lisp/term/xterm.el, lisp/vc/vc-git.el:
* lisp/vc/vc-hg.el, lisp/x-dnd.el, test/src/data-tests.el:
Prefer ash to lsh when either will do.
Diffstat (limited to 'lisp/net/dns.el')
-rw-r--r-- | lisp/net/dns.el | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/lisp/net/dns.el b/lisp/net/dns.el index 057ae3219ee..b3b430d2ba8 100644 --- a/lisp/net/dns.el +++ b/lisp/net/dns.el @@ -117,7 +117,7 @@ updated. Set this variable to t to disable the check.") length) (while (not ended) (setq length (dns-read-bytes 1)) - (if (= 192 (logand length (lsh 3 6))) + (if (= 192 (logand length (ash 3 6))) (let ((offset (+ (* (logand 63 length) 256) (dns-read-bytes 1)))) (save-excursion @@ -144,17 +144,17 @@ If TCP-P, the first two bytes of the package with be the length field." (dns-write-bytes (dns-get 'id spec) 2) (dns-write-bytes (logior - (lsh (if (dns-get 'response-p spec) 1 0) -7) - (lsh + (ash (if (dns-get 'response-p spec) 1 0) 7) + (ash (cond ((eq (dns-get 'opcode spec) 'query) 0) ((eq (dns-get 'opcode spec) 'inverse-query) 1) ((eq (dns-get 'opcode spec) 'status) 2) (t (error "No such opcode: %s" (dns-get 'opcode spec)))) - -3) - (lsh (if (dns-get 'authoritative-p spec) 1 0) -2) - (lsh (if (dns-get 'truncated-p spec) 1 0) -1) - (lsh (if (dns-get 'recursion-desired-p spec) 1 0) 0))) + 3) + (ash (if (dns-get 'authoritative-p spec) 1 0) 2) + (ash (if (dns-get 'truncated-p spec) 1 0) 1) + (ash (if (dns-get 'recursion-desired-p spec) 1 0) 0))) (dns-write-bytes (cond ((eq (dns-get 'response-code spec) 'no-error) 0) @@ -198,20 +198,20 @@ If TCP-P, the first two bytes of the package with be the length field." (goto-char (point-min)) (push (list 'id (dns-read-bytes 2)) spec) (let ((byte (dns-read-bytes 1))) - (push (list 'response-p (if (zerop (logand byte (lsh 1 7))) nil t)) + (push (list 'response-p (if (zerop (logand byte (ash 1 7))) nil t)) spec) - (let ((opcode (logand byte (lsh 7 3)))) + (let ((opcode (logand byte (ash 7 3)))) (push (list 'opcode (cond ((eq opcode 0) 'query) ((eq opcode 1) 'inverse-query) ((eq opcode 2) 'status))) spec)) - (push (list 'authoritative-p (if (zerop (logand byte (lsh 1 2))) + (push (list 'authoritative-p (if (zerop (logand byte (ash 1 2))) nil t)) spec) - (push (list 'truncated-p (if (zerop (logand byte (lsh 1 2))) nil t)) + (push (list 'truncated-p (if (zerop (logand byte (ash 1 2))) nil t)) spec) (push (list 'recursion-desired-p - (if (zerop (logand byte (lsh 1 0))) nil t)) spec)) + (if (zerop (logand byte (ash 1 0))) nil t)) spec)) (let ((rc (logand (dns-read-bytes 1) 15))) (push (list 'response-code (cond |