sysctl: fix file parsing, do not require -w for VAR=VAL

function                                             old     new   delta
sysctl_act_on_setting                                  -     451    +451
sysctl_main                                          222     282     +60
packed_usage                                       31744   31793     +49
config_read                                          604     639     +35
sysctl_act_recursive                                 612     163    -449
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 3/1 up/down: 595/-449)          Total: 146 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2017-08-05 13:45:22 +02:00
parent feb79e8742
commit 9cf89cdf84
4 changed files with 77 additions and 32 deletions

View File

@ -201,10 +201,10 @@ int FAST_FUNC config_read(parser_t *parser, char **tokens, unsigned flags, const
/* Combine remaining arguments? */ /* Combine remaining arguments? */
if ((t != (ntokens-1)) || !(flags & PARSE_GREEDY)) { if ((t != (ntokens-1)) || !(flags & PARSE_GREEDY)) {
/* Vanilla token, find next delimiter */ /* Vanilla token, find next delimiter */
line += strcspn(line, delims[0] ? delims : delims + 1); line += strcspn(line, (delims[0] && (flags & PARSE_EOL_COMMENTS)) ? delims : delims + 1);
} else { } else {
/* Combining, find comment char if any */ /* Combining, find comment char if any */
line = strchrnul(line, PARSE_EOL_COMMENTS ? delims[0] : '\0'); line = strchrnul(line, (flags & PARSE_EOL_COMMENTS) ? delims[0] : '\0');
/* Trim any extra delimiters from the end */ /* Trim any extra delimiters from the end */
if (flags & PARSE_TRIM) { if (flags & PARSE_TRIM) {
@ -214,10 +214,10 @@ int FAST_FUNC config_read(parser_t *parser, char **tokens, unsigned flags, const
} }
/* Token not terminated? */ /* Token not terminated? */
if (*line == delims[0]) if ((flags & PARSE_EOL_COMMENTS) && *line == delims[0])
*line = '\0'; *line = '\0'; /* ends with comment char: this line is done */
else if (*line != '\0') else if (*line != '\0')
*line++ = '\0'; *line++ = '\0'; /* token is done, continue parsing line */
#if 0 /* unused so far */ #if 0 /* unused so far */
if (flags & PARSE_ESCAPE) { if (flags & PARSE_ESCAPE) {

View File

@ -21,17 +21,17 @@
//kbuild:lib-$(CONFIG_BB_SYSCTL) += sysctl.o //kbuild:lib-$(CONFIG_BB_SYSCTL) += sysctl.o
//usage:#define sysctl_trivial_usage //usage:#define sysctl_trivial_usage
//usage: "[OPTIONS] [KEY[=VALUE]]..." //usage: "-p [-enq] [FILE...] / [-enqaw] [KEY[=VALUE]]..."
//usage:#define sysctl_full_usage "\n\n" //usage:#define sysctl_full_usage "\n\n"
//usage: "Show/set kernel parameters\n" //usage: "Show/set kernel parameters\n"
//usage: "\n -p Set values from FILEs (default /etc/sysctl.conf)"
//usage: "\n -e Don't warn about unknown keys" //usage: "\n -e Don't warn about unknown keys"
//usage: "\n -n Don't show key names" //usage: "\n -n Don't show key names"
//usage: "\n -q Quiet"
//usage: "\n -a Show all values" //usage: "\n -a Show all values"
/* Same as -a, no need to show it */ /* Same as -a, no need to show it */
/* //usage: "\n -A Show all values in table form" */ /* //usage: "\n -A Show all values in table form" */
//usage: "\n -w Set values" //usage: "\n -w Set values"
//usage: "\n -p FILE Set values from FILE (default /etc/sysctl.conf)"
//usage: "\n -q Set values silently"
//usage: //usage:
//usage:#define sysctl_example_usage //usage:#define sysctl_example_usage
//usage: "sysctl [-n] [-e] variable...\n" //usage: "sysctl [-n] [-e] variable...\n"
@ -48,7 +48,7 @@ enum {
FLAG_TABLE_FORMAT = 1 << 2, /* not implemented */ FLAG_TABLE_FORMAT = 1 << 2, /* not implemented */
FLAG_SHOW_ALL = 1 << 3, FLAG_SHOW_ALL = 1 << 3,
FLAG_PRELOAD_FILE = 1 << 4, FLAG_PRELOAD_FILE = 1 << 4,
/* TODO: procps 3.2.8 seems to not require -w for KEY=VAL to work: */ /* NB: procps 3.2.8 does not require -w for KEY=VAL to work, it only rejects non-KEY=VAL form */
FLAG_WRITE = 1 << 5, FLAG_WRITE = 1 << 5,
FLAG_QUIET = 1 << 6, FLAG_QUIET = 1 << 6,
}; };
@ -104,6 +104,7 @@ static int sysctl_act_on_setting(char *setting)
int fd, retval = EXIT_SUCCESS; int fd, retval = EXIT_SUCCESS;
char *cptr, *outname; char *cptr, *outname;
char *value = value; /* for compiler */ char *value = value; /* for compiler */
bool writing = (option_mask32 & FLAG_WRITE);
outname = xstrdup(setting); outname = xstrdup(setting);
@ -114,8 +115,10 @@ static int sysctl_act_on_setting(char *setting)
cptr++; cptr++;
} }
if (option_mask32 & FLAG_WRITE) {
cptr = strchr(setting, '='); cptr = strchr(setting, '=');
if (cptr)
writing = 1;
if (writing) {
if (cptr == NULL) { if (cptr == NULL) {
bb_error_msg("error: '%s' must be of the form name=value", bb_error_msg("error: '%s' must be of the form name=value",
outname); outname);
@ -147,7 +150,7 @@ static int sysctl_act_on_setting(char *setting)
break; break;
default: default:
bb_perror_msg("error %sing key '%s'", bb_perror_msg("error %sing key '%s'",
option_mask32 & FLAG_WRITE ? writing ?
"sett" : "read", "sett" : "read",
outname); outname);
break; break;
@ -156,7 +159,7 @@ static int sysctl_act_on_setting(char *setting)
goto end; goto end;
} }
if (option_mask32 & FLAG_WRITE) { if (writing) {
//TODO: procps 3.2.7 writes "value\n", note trailing "\n" //TODO: procps 3.2.7 writes "value\n", note trailing "\n"
xwrite_str(fd, value); xwrite_str(fd, value);
close(fd); close(fd);
@ -238,22 +241,27 @@ static int sysctl_handle_preload_file(const char *filename)
{ {
char *token[2]; char *token[2];
parser_t *parser; parser_t *parser;
int parse_flags;
parser = config_open(filename); parser = config_open(filename);
/* Must do it _after_ config_open(): */ /* Must do it _after_ config_open(): */
xchdir("/proc/sys"); xchdir("/proc/sys");
/* xchroot("/proc/sys") - if you are paranoid */
//TODO: ';' is comment char too //TODO: ';' is comment char too
//TODO: comment may be only at line start. "var=1 #abc" - "1 #abc" is the value //TODO: <space><tab><space>#comment is also comment, not strictly 1st char only
// (but _whitespace_ from ends should be trimmed first (and we do it right)) parse_flags = 0;
//TODO: "var==1" is mishandled (must use "=1" as a value, but uses "1") parse_flags &= ~PARSE_COLLAPSE; // NO (var==val is not var=val) - treat consecutive delimiters as one
// can it be fixed by removing PARSE_COLLAPSE bit? parse_flags &= ~PARSE_TRIM; // NO - trim leading and trailing delimiters
while (config_read(parser, token, 2, 2, "# \t=", PARSE_NORMAL)) { parse_flags |= PARSE_GREEDY; // YES - last token takes entire remainder of the line
parse_flags &= ~PARSE_MIN_DIE; // NO - die if < min tokens found
parse_flags &= ~PARSE_EOL_COMMENTS; // NO (only first char) - comments are recognized even if not first char
while (config_read(parser, token, 2, 2, "#=", parse_flags)) {
char *tp; char *tp;
trim(token[0]);
trim(token[1]);
sysctl_dots_to_slashes(token[0]); sysctl_dots_to_slashes(token[0]);
tp = xasprintf("%s=%s", token[0], token[1]); tp = xasprintf("%s=%s", token[0], token[1]);
sysctl_act_recursive(tp); sysctl_act_on_setting(tp);
free(tp); free(tp);
} }
if (ENABLE_FEATURE_CLEAN_UP) if (ENABLE_FEATURE_CLEAN_UP)
@ -273,12 +281,19 @@ int sysctl_main(int argc UNUSED_PARAM, char **argv)
option_mask32 = opt; option_mask32 = opt;
if (opt & FLAG_PRELOAD_FILE) { if (opt & FLAG_PRELOAD_FILE) {
int cur_dir_fd;
option_mask32 |= FLAG_WRITE; option_mask32 |= FLAG_WRITE;
if (!*argv)
*--argv = (char*)"/etc/sysctl.conf";
cur_dir_fd = xopen(".", O_RDONLY | O_DIRECTORY);
do {
/* xchdir("/proc/sys") is inside */ /* xchdir("/proc/sys") is inside */
return sysctl_handle_preload_file(*argv ? *argv : "/etc/sysctl.conf"); sysctl_handle_preload_file(*argv);
xfchdir(cur_dir_fd); /* files can be relative, must restore cwd */
} while (*++argv);
return 0; /* procps-ng 3.3.10 does not flag parse errors */
} }
xchdir("/proc/sys"); xchdir("/proc/sys");
/* xchroot("/proc/sys") - if you are paranoid */
if (opt & (FLAG_TABLE_FORMAT | FLAG_SHOW_ALL)) { if (opt & (FLAG_TABLE_FORMAT | FLAG_SHOW_ALL)) {
return sysctl_act_recursive("."); return sysctl_act_recursive(".");
} }

View File

@ -168,7 +168,7 @@ SKIP=
# continuing to use directory structure from prev test # continuing to use directory structure from prev test
rm -rf mdev.testdir/dev/* rm -rf mdev.testdir/dev/*
echo "sda 0:0 644 @echo @echo TEST" >mdev.testdir/etc/mdev.conf echo "sda 0:0 644 @echo @echo TEST" >mdev.testdir/etc/mdev.conf
optional STATIC FEATURE_MDEV_CONF FEATURE_MDEV_EXEC FEATURE_LS_RECURSIVE FEATURE_LS_TIMESTAMPS FEATURE_LS_USERNAME FEATURE_SH_IS_ASH ASH_ECHO optional STATIC FEATURE_MDEV_CONF FEATURE_MDEV_EXEC FEATURE_LS_RECURSIVE FEATURE_LS_TIMESTAMPS FEATURE_LS_USERNAME SH_IS_ASH ASH_ECHO
testing "mdev command" \ testing "mdev command" \
"env - PATH=$PATH ACTION=add DEVPATH=/block/sda chroot mdev.testdir /mdev 2>&1; "env - PATH=$PATH ACTION=add DEVPATH=/block/sda chroot mdev.testdir /mdev 2>&1;
ls -lnR mdev.testdir/dev | $FILTER_LS" \ ls -lnR mdev.testdir/dev | $FILTER_LS" \
@ -183,7 +183,7 @@ SKIP=
# continuing to use directory structure from prev test # continuing to use directory structure from prev test
rm -rf mdev.testdir/dev/* rm -rf mdev.testdir/dev/*
echo "sda 0:0 644 =block/ @echo @echo TEST:\$MDEV" >mdev.testdir/etc/mdev.conf echo "sda 0:0 644 =block/ @echo @echo TEST:\$MDEV" >mdev.testdir/etc/mdev.conf
optional STATIC FEATURE_MDEV_CONF FEATURE_MDEV_RENAME FEATURE_MDEV_EXEC FEATURE_LS_RECURSIVE FEATURE_LS_TIMESTAMPS FEATURE_LS_USERNAME FEATURE_SH_IS_ASH optional STATIC FEATURE_MDEV_CONF FEATURE_MDEV_RENAME FEATURE_MDEV_EXEC FEATURE_LS_RECURSIVE FEATURE_LS_TIMESTAMPS FEATURE_LS_USERNAME SH_IS_ASH
testing "mdev move and command" \ testing "mdev move and command" \
"env - PATH=$PATH ACTION=add DEVPATH=/block/sda chroot mdev.testdir /mdev 2>&1; "env - PATH=$PATH ACTION=add DEVPATH=/block/sda chroot mdev.testdir /mdev 2>&1;
ls -lnR mdev.testdir/dev | $FILTER_LS2" \ ls -lnR mdev.testdir/dev | $FILTER_LS2" \

View File

@ -10,8 +10,8 @@ TRIM=$(( 0x00020000))
GREEDY=$(( 0x00040000)) GREEDY=$(( 0x00040000))
MIN_DIE=$(( 0x00100000)) MIN_DIE=$(( 0x00100000))
KEEP_COPY=$(( 0x00200000)) KEEP_COPY=$(( 0x00200000))
ESCAPE=$(( 0x00400000)) EOL_COMMENTS=$((0x00400000))
NORMAL=$(( COLLAPSE | TRIM | GREEDY)) NORMAL=$(( COLLAPSE | TRIM | GREEDY | EOL_COMMENTS))
# testing "description" "command" "result" "infile" "stdin" # testing "description" "command" "result" "infile" "stdin"
@ -27,6 +27,34 @@ testing "parse notrim" \
"-" \ "-" \
" sda 0:0 644 @echo @echo TEST \n" " sda 0:0 644 @echo @echo TEST \n"
testing "parse comments" \
"parse -n 4 -m 3 -f $((NORMAL - EOL_COMMENTS)) -" \
"[sda][0:0][644][@echo @echo TEST #this is not eaten]\n" \
"-" \
"\
# sda 0:0 644 @echo @echo TEST - this gets eaten
sda 0:0 644 @echo @echo TEST #this is not eaten
"
testing "parse bad comment" \
"parse -n 2 -m 2 -d '#=' -f $((GREEDY)) - 2>&1" \
"\
[var][val]
parse: bad line 3: 1 tokens found, 2 needed
[ #this][ok]
[ #this][=ok]
[ #this][=ok=ok=ok=]
" \
"-" \
"\
# this gets eaten
var=val
#this causes error msg
#this=ok
#this==ok
#this==ok=ok=ok=
"
FILE=__parse FILE=__parse
cat >$FILE <<EOF cat >$FILE <<EOF
# #
@ -96,6 +124,8 @@ cat >$FILE.res <<EOF
[option][dns][129.219.13.81] [option][dns][129.219.13.81]
[option][domain][local] [option][domain][local]
[option][lease][864000] [option][lease][864000]
[option][msstaticroutes][10.0.0.0/8][10.127.0.1]
[option][staticroutes][10.0.0.0/8][10.127.0.1,][10.11.12.0/24][10.11.12.1]
[option][0x08][01020304] [option][0x08][01020304]
EOF EOF