glibc/scripts/gen-tunables.awk
Adhemerval Zanella a4c3f5f46e elf: Add a way to check if tunable is set (BZ 27069)
The patch adds two new macros, TUNABLE_GET_DEFAULT and TUNABLE_IS_INITIALIZED,
here the former get the default value with a signature similar to
TUNABLE_GET, while the later returns whether the tunable was set by
the environment variable.

Checked on x86_64-linux-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
2023-11-29 09:30:00 -03:00

173 lines
4.1 KiB
Awk

# Generate dl-tunable-list.h from dl-tunables.list
BEGIN {
min_of["STRING"]="0"
max_of["STRING"]="0"
min_of["INT_32"]="INT32_MIN"
max_of["INT_32"]="INT32_MAX"
min_of["UINT_64"]="0"
max_of["UINT_64"]="UINT64_MAX"
min_of["SIZE_T"]="0"
max_of["SIZE_T"]="SIZE_MAX"
tunable=""
ns=""
top_ns=""
max_name_len=0
max_alias_len=0
}
# Skip over blank lines and comments.
/^#/ {
next
}
/^[ \t]*$/ {
next
}
# Beginning of either a top namespace, tunable namespace or a tunable, decided
# on the current value of TUNABLE, NS or TOP_NS.
$2 == "{" {
if (top_ns == "") {
top_ns = $1
}
else if (ns == "") {
ns = $1
}
else if (tunable == "") {
tunable = $1
}
else {
printf ("Unexpected occurrence of '{': %s:%d\n", FILENAME, FNR)
exit 1
}
next
}
# End of either a top namespace, tunable namespace or a tunable.
$1 == "}" {
if (tunable != "") {
# Tunables definition ended, now fill in default attributes.
if (!types[top_ns,ns,tunable]) {
types[top_ns,ns,tunable] = "STRING"
}
if (!minvals[top_ns,ns,tunable]) {
minvals[top_ns,ns,tunable] = min_of[types[top_ns,ns,tunable]]
}
if (!maxvals[top_ns,ns,tunable]) {
maxvals[top_ns,ns,tunable] = max_of[types[top_ns,ns,tunable]]
}
if (!env_alias[top_ns,ns,tunable]) {
env_alias[top_ns,ns,tunable] = "{0}"
}
len = length(top_ns"."ns"."tunable)
if (len > max_name_len)
max_name_len = len
tunable = ""
}
else if (ns != "") {
ns = ""
}
else if (top_ns != "") {
top_ns = ""
}
else {
printf ("syntax error: extra }: %s:%d\n", FILENAME, FNR)
exit 1
}
next
}
# Everything else, which could either be a tunable without any attributes or a
# tunable attribute.
{
if (ns == "") {
printf("Line %d: Invalid tunable outside a namespace: %s\n", NR, $0)
exit 1
}
if (tunable == "") {
# We encountered a tunable without any attributes, so note it with a
# default.
types[top_ns,ns,$1] = "STRING"
next
}
# Otherwise, we have encountered a tunable attribute.
split($0, arr, ":")
attr = gensub(/^[ \t]+|[ \t]+$/, "", "g", arr[1])
val = gensub(/^[ \t]+|[ \t]+$/, "", "g", arr[2])
if (attr == "type") {
types[top_ns,ns,tunable] = val
}
else if (attr == "minval") {
minvals[top_ns,ns,tunable] = val
}
else if (attr == "maxval") {
maxvals[top_ns,ns,tunable] = val
}
else if (attr == "env_alias") {
env_alias[top_ns,ns,tunable] = sprintf("\"%s\"", val)
len = length(val)
if (len > max_alias_len)
max_alias_len = len
}
else if (attr == "default") {
if (types[top_ns,ns,tunable] == "STRING") {
default_val[top_ns,ns,tunable] = sprintf(".strval = \"%s\"", val);
}
else {
default_val[top_ns,ns,tunable] = sprintf(".numval = %s", val)
}
}
}
END {
if (ns != "") {
print "Unterminated namespace. Is a closing brace missing?"
exit 1
}
print "/* AUTOGENERATED by gen-tunables.awk. */"
print "#ifndef _TUNABLES_H_"
print "# error \"Do not include this file directly.\""
print "# error \"Include tunables.h instead.\""
print "#endif"
print "#include <dl-procinfo.h>\n"
# Now, the enum names
print "\ntypedef enum"
print "{"
for (tnm in types) {
split (tnm, indices, SUBSEP);
t = indices[1];
n = indices[2];
m = indices[3];
printf (" TUNABLE_ENUM_NAME(%s, %s, %s),\n", t, n, m);
}
print "} tunable_id_t;\n"
print "\n#ifdef TUNABLES_INTERNAL"
# Internal definitions.
print "# define TUNABLE_NAME_MAX " (max_name_len + 1)
print "# define TUNABLE_ALIAS_MAX " (max_alias_len + 1)
print "# include \"dl-tunable-types.h\""
# Finally, the tunable list.
print "static tunable_t tunable_list[] attribute_relro = {"
for (tnm in types) {
split (tnm, indices, SUBSEP);
t = indices[1];
n = indices[2];
m = indices[3];
printf (" {TUNABLE_NAME_S(%s, %s, %s)", t, n, m)
printf (", {TUNABLE_TYPE_%s, %s, %s}, {%s}, {%s}, false, %s},\n",
types[t,n,m], minvals[t,n,m], maxvals[t,n,m], default_val[t,n,m],
default_val[t,n,m], env_alias[t,n,m]);
}
print "};"
print "#endif"
}