Fix some issues at get_abi.pl script

This series replace this patch:

	https://lore.kernel.org/linux-doc/[email protected]/T/#t

It turns that there were multiple bugs at the get_abi.pl code that create cross-references.

Patches 1 to 6 fix those issues, and should apply cleanly on the top of the docs tree (although I tested against next-20210323).

Patch 7 is optional, and independent from the other patches. It is meant to be applied against akpm's tree. It makes the description (IMHO) clearer, while producing cross references for the two mentioned symbols.

The fix patches are:

patch 1: fix some regexes that match the symbols that need to be
escaped when parsing "What:". The same regex is also used when generating cross-references;

patch 2: makes the check for Documentation/ABI references more
robust, as right now, it stops at the first occurrence;

patch 3: fix the parser for /sys/foo -> xref conversion. Basically,
the logic that seeks for start and end boundaries were broken. The new logic is a way more robust.

patch 4: generate cross-references for /config/foo and other less
common ABI occurrences;

patch 5 and 6: don't generate cross-references inside literal blocks.
Right now, there are a couple of places that would otherwise generate references, producing a bad output.

Mauro Carvalho Chehab (7):
scripts: get_abi.pl: better handle escape chars on what:
get_abi.pl: seek for all occurrences for Documentation/ABI get_abi.pl: fix xref boundaries
scripts: get_abi.pl: extend xref match to other types
scripts: get_abi.pl: parse description line per line
scripts: get_abi: ignore code blocks for cross-references
ABI: sysfs-kernel-mm-cma: fix two cross-references

 Documentation/ABI/testing/sysfs-kernel-mm-cma |  8 +-
 scripts/get_abi.pl                            | 76 +++++++++++++------
 2 files changed, 57 insertions(+), 27 deletions(-)

2.30.2

The parser for the symbols defined on What: doesn't cover all chars that need to be scaped, like '{' and '}'. Change the logic to be more generic, and ensure that the same regex will be used on both What: and when parsing the cross-references.

---
 scripts/get_abi.pl | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

index 92d9aa6cc4f5..a9348b9bdaa4 100755
@@ -283,6 +283,7 @@ sub create_labels {
 
 # \b doesn't work well with paths. So, we need to define something else
 my $bondary = qr { (?<![\w\/\`\{])(?=[\w\/\`\{])|(?<=[\w\/\`\{])(?![\w\/\`\{]) }x;
+my $symbols = qr { ([\x01-\x08\x0e-\x1f\x21-\x2f\x3a-\x40\x7b-\xff]) }x;
 
 sub output_rest {
 	create_labels();

@@ -305,7 +306,6 @@ sub output_rest {
 		}
 
 		my $w = $what;
-		$w =~ s/([\(\)\_\-\*\=\^\~\\])/\\$1/g;
 
 		if ($type ne "File") {
 			my $cur_part = $what;

@@ -329,6 +329,7 @@ sub output_rest {
 			my $len = 0;
 
 			foreach my $name (@names) {
+				$name =~ s/$symbols/\\$1/g;
 				$name = "**$name**";
 				$len = length($name) if (length($name) > $len);
 			}

@@ -395,7 +396,7 @@ sub output_rest {
 					if (defined($data{$s}) && defined($data{$s}->{label})) {
 						my $xref = $s;
 
-						$xref =~ s/([\x00-\x1f\x21-\x2f\x3a-\x40\x7b-\xff])/\\$1/g;
+						$xref =~ s/$symbols/\\$1/g;
 						$xref = ":ref:`$xref <" . $data{$s}->{label} . ">`";
 
 						$desc =~ s,$bondary$s$bondary,$xref,g;

2.30.2

Instead of retrieving just one match at most, ensure that the entire description will be parsed.

---
 scripts/get_abi.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index a9348b9bdaa4..3c82cd188368 100755
@@ -380,7 +380,7 @@ sub output_rest {
 
 				$desc =~ s,Documentation/(?!devicetree)(\S+)\.rst,:doc:`/$1`,g;
 
-				my @matches = $desc =~ m,Documentation/ABI/([\w\/\-]+),;
+				my @matches = $desc =~ m,Documentation/ABI/([\w\/\-]+),g;
 				foreach my $f (@matches) {
 					my $xref = $f;
 					my $path = $f;

2.30.2

There are some issues with the regex that seeks for What:
cross references: basically, it is mis-identifying the start and the end boundaries of the regex, which causes :ref: to be inseerted for the wrong symbols at the wrong places.

Fix it.

---
 scripts/get_abi.pl | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

index 3c82cd188368..e87028257d1c 100755
@@ -281,8 +281,11 @@ sub create_labels {
 # Outputs the book on ReST format
 #
 
-# \b doesn't work well with paths. So, we need to define something else
-my $bondary = qr { (?<![\w\/\`\{])(?=[\w\/\`\{])|(?<=[\w\/\`\{])(?![\w\/\`\{]) }x;
+# \b doesn't work well with paths. So, we need to define something else:
+# Boundaries are punct characters, spaces and end-of-line
+my $start = qr {(^|\s|\() }x;
+my $bondary = qr { ([,.:;\)\s]|\z) }x;
+my $xref_match = qr { $start(\/sys\/[^,.:;\)\s]+)$bondary }x;
 my $symbols = qr { ([\x01-\x08\x0e-\x1f\x21-\x2f\x3a-\x40\x7b-\xff]) }x;
 
 sub output_rest {

@@ -390,16 +393,18 @@ sub output_rest {
 					$desc =~ s,\bDocumentation/ABI/$f\b,:ref:`$xref`,g;
 				}
 
-				@matches = $desc =~ m,$bondary(/sys/[^\s\.\,\;\:\*\s\`\'\(\)]+)$bondary,;
+				# Seek for cross reference symbols like /sys/...
+				@matches = $desc =~ m/$xref_match/g;
 
 				foreach my $s (@matches) {
+					next if (!($s =~ m,/,));
 					if (defined($data{$s}) && defined($data{$s}->{label})) {
 						my $xref = $s;
 
 						$xref =~ s/$symbols/\\$1/g;
 						$xref = ":ref:`$xref <" . $data{$s}->{label} . ">`";
 
-						$desc =~ s,$bondary$s$bondary,$xref,g;
+						$desc =~ s,$start$s$bondary,$1$xref$2,g;
 					}
 				}
 

2.30.2

Currently, there are "What:" symbols for more than just /sys.

Extend the regex to also cover configfs, /proc /dev and /kvd symbols.

---
 scripts/get_abi.pl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index e87028257d1c..eb1a23103afa 100755
@@ -285,7 +285,7 @@ sub create_labels {
 # Boundaries are punct characters, spaces and end-of-line
 my $start = qr {(^|\s|\() }x;
 my $bondary = qr { ([,.:;\)\s]|\z) }x;
-my $xref_match = qr { $start(\/sys\/[^,.:;\)\s]+)$bondary }x;
+my $xref_match = qr { $start(\/(sys|config|proc|dev|kvd)\/[^,.:;\)\s]+)$bondary }x;
 my $symbols = qr { ([\x01-\x08\x0e-\x1f\x21-\x2f\x3a-\x40\x7b-\xff]) }x;
 
 sub output_rest {

2.30.2

Change the description parsing logic in rst mode in order to parse it line per line.

The end result is the same, but doing line per line allows to add some code to escape literal blocks when seeking for cross-references.

---
 scripts/get_abi.pl | 47 ++++++++++++++++++++++++++--------------------
 1 file changed, 27 insertions(+), 20 deletions(-)

index eb1a23103afa..e5d1da492c1e 100755
@@ -381,34 +381,41 @@ sub output_rest {
 
 				# Enrich text by creating cross-references
 
-				$desc =~ s,Documentation/(?!devicetree)(\S+)\.rst,:doc:`/$1`,g;
+				my $new_desc = "";
+				open(my $fh, "+<", \$desc);
+				while (my $d = <$fh>) {
+					$d =~ s,Documentation/(?!devicetree)(\S+)\.rst,:doc:`/$1`,g;
 
-				my @matches = $desc =~ m,Documentation/ABI/([\w\/\-]+),g;
-				foreach my $f (@matches) {
-					my $xref = $f;
-					my $path = $f;
-					$path =~ s,.*/(.*/.*),$1,;;
-					$path =~ s,[/\-],_,g;;
-					$xref .= " <abi_file_" . $path . ">";
-					$desc =~ s,\bDocumentation/ABI/$f\b,:ref:`$xref`,g;
-				}
+					my @matches = $d =~ m,Documentation/ABI/([\w\/\-]+),g;
+					foreach my $f (@matches) {
+						my $xref = $f;
+						my $path = $f;
+						$path =~ s,.*/(.*/.*),$1,;;
+						$path =~ s,[/\-],_,g;;
+						$xref .= " <abi_file_" . $path . ">";
+						$d =~ s,\bDocumentation/ABI/$f\b,:ref:`$xref`,g;
+					}
 
-				# Seek for cross reference symbols like /sys/...
-				@matches = $desc =~ m/$xref_match/g;
+					# Seek for cross reference symbols like /sys/...
+					@matches = $d =~ m/$xref_match/g;
 
-				foreach my $s (@matches) {
-					next if (!($s =~ m,/,));
-					if (defined($data{$s}) && defined($data{$s}->{label})) {
-						my $xref = $s;
+					foreach my $s (@matches) {
+						next if (!($s =~ m,/,));
+						if (defined($data{$s}) && defined($data{$s}->{label})) {
+							my $xref = $s;
 
-						$xref =~ s/$symbols/\\$1/g;
-						$xref = ":ref:`$xref <" . $data{$s}->{label} . ">`";
+							$xref =~ s/$symbols/\\$1/g;
+							$xref = ":ref:`$xref <" . $data{$s}->{label} . ">`";
 
-						$desc =~ s,$start$s$bondary,$1$xref$2,g;
+							$d =~ s,$start$s$bondary,$1$xref$2,g;
+						}
 					}
+					$new_desc .= $d;
 				}
+				close $fh;
+
 
-				print "$desc\n\n";
+				print "$new_desc\n\n";
 			} else {
 				$desc =~ s/^\s+//;
 

2.30.2

The script should not generate cross-references inside literal blocks.

---
 scripts/get_abi.pl | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

index e5d1da492c1e..d7aa82094296 100755
@@ -382,8 +382,27 @@ sub output_rest {
 				# Enrich text by creating cross-references
 
 				my $new_desc = "";
+				my $init_indent = -1;
+				my $literal_indent = -1;
+
 				open(my $fh, "+<", \$desc);
 				while (my $d = <$fh>) {
+					my $indent = $d =~ m/^(\s+)/;
+					my $spaces = length($indent);
+					$init_indent = $indent if ($init_indent < 0);
+					if ($literal_indent >= 0) {
+						if ($spaces > $literal_indent) {
+							$new_desc .= $d;
+							next;
+						} else {
+							$literal_indent = -1;
+						}
+					} else {
+						if ($d =~ /()::$/ && !($d =~ /^\s*\.\./)) {
+							$literal_indent = $spaces;
+						}
+					}
+
 					$d =~ s,Documentation/(?!devicetree)(\S+)\.rst,:doc:`/$1`,g;
 
 					my @matches = $d =~ m,Documentation/ABI/([\w\/\-]+),g;

2.30.2

Change the text in order to generate cross-references for alloc_pages_success and alloc_pages_fail symbols.

---
 Documentation/ABI/testing/sysfs-kernel-mm-cma | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

index 02b2bb60c296..86e261185561 100644
@@ -5,12 +5,10 @@ Description:
 		/sys/kernel/mm/cma/ contains a subdirectory for each CMA
 		heap name (also sometimes called CMA areas).
 
-		Each CMA heap subdirectory (that is, each
-		/sys/kernel/mm/cma/<cma-heap-name> directory) contains the
-		following items:
+		Each CMA heap subdirectory contains the following items:
 
-			alloc_pages_success
-			alloc_pages_fail
+			- /sys/kernel/mm/cma/<cma-heap-name>/alloc_pages_success
+			- /sys/kernel/mm/cma/<cma-heap-name>/alloc_pages_fail
 
 What:		/sys/kernel/mm/cma/<cma-heap-name>/alloc_pages_success
 Date:		Feb 2021

2.30.2

So perhaps this is the best solution to the problem, but I must confess to not being entirely happy with it. get_abi.pl is becoming another unreadable perlpile like kerneldoc, and this makes it worse. Doing RST parsing there seems particularly unwelcome.

Should the cross-reference generation, it now occurs to me, be done in the automarkup module instead? Then there's no need to interpret RST, and we'd get cross-references throughout the kernel docs rather than in just the ABI stuff. Am I completely out to lunch here?

Thanks,

jon

Em Thu, 25 Mar 2021 13:01:14 -0600
Jonathan Corbet <[email protected]> escreveu:

Nah, it is not that complex ;-)
It has 628 lines of code; kernel-doc has 2488. It is 1/4 the size of kernel-doc :-D

Btw, 20 lines can be removed from it, if we drop support for --no-rst-source. I almost dropped it this time :-)

Ah, the entire code that outputs the rst description and does the xref has just 34 lines (with 5 lines with comments and 5 blank lines).

It is not much, and some cleanups could be done to make it a little shorter.

Most of the script complexity is actually at the parsing part. The thing is that the ABI files are somewhat free-style: some files don't strictly follow the format, which requires some extra steps in order to cope with some "soft" violations, as well as to report problems when the violation is more severe.

Yes, I guess we can move the Xref code to automarkup some day, that is if we can ensure that get_abi.pl will run before automarkup.

There's currently an issue, though. We need first to get rid of those duplicated symbols:

	Warning: /sys/bus/iio/devices/iio:deviceX/in_accel_x_calibbias is defined 2 times:  Documentation/ABI/testing/sysfs-bus-iio-icm42600:0  Documentation/ABI/testing/sysfs-bus-iio:395
	Warning: /sys/bus/iio/devices/iio:deviceX/in_accel_y_calibbias is defined 2 times:  Documentation/ABI/testing/sysfs-bus-iio-icm42600:1  Documentation/ABI/testing/sysfs-bus-iio:396
	Warning: /sys/bus/iio/devices/iio:deviceX/in_accel_z_calibbias is defined 2 times:  Documentation/ABI/testing/sysfs-bus-iio-icm42600:2  Documentation/ABI/testing/sysfs-bus-iio:397
	Warning: /sys/bus/iio/devices/iio:deviceX/in_anglvel_x_calibbias is defined 2 times:  Documentation/ABI/testing/sysfs-bus-iio-icm42600:3  Documentation/ABI/testing/sysfs-bus-iio:398
	Warning: /sys/bus/iio/devices/iio:deviceX/in_anglvel_y_calibbias is defined 2 times:  Documentation/ABI/testing/sysfs-bus-iio-icm42600:4  Documentation/ABI/testing/sysfs-bus-iio:399
	Warning: /sys/bus/iio/devices/iio:deviceX/in_anglvel_z_calibbias is defined 2 times:  Documentation/ABI/testing/sysfs-bus-iio-icm42600:5  Documentation/ABI/testing/sysfs-bus-iio:400

Warning: /sys/bus/iio/devices/iio:deviceX/in_count0_preset is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-timer-stm32:100 Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32:0
Warning: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-counter-104-quad-8:2 Documentation/ABI/testing/sysfs-bus-iio-lptimer-stm32:8
Warning: /sys/bus/iio/devices/iio:deviceX/out_altvoltageY_frequency is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4371:0 Documentation/ABI/testing/sysfs-bus-iio:600
Warning: /sys/bus/iio/devices/iio:deviceX/out_altvoltageY_powerdown is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-frequency-adf4371:36 Documentation/ABI/testing/sysfs-bus-iio:589
Warning: /sys/bus/iio/devices/iio:deviceX/out_currentY_raw is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-light-lm3533-als:43 Documentation/ABI/testing/sysfs-bus-iio-health-afe440x:38
Warning: /sys/bus/iio/devices/iio:deviceX/out_current_heater_raw is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc2010:0 Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc100x:0
Warning: /sys/bus/iio/devices/iio:deviceX/out_current_heater_raw_available is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc2010:1 Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc100x:1
Warning: /sys/bus/iio/devices/iio:deviceX/sensor_sensitivity is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-distance-srf08:0 Documentation/ABI/testing/sysfs-bus-iio-proximity-as3935:8
Warning: /sys/bus/iio/devices/triggerX/sampling_frequency is defined 2 times: Documentation/ABI/testing/sysfs-bus-iio-timer-stm32:92 Documentation/ABI/testing/sysfs-bus-iio:45
Warning: /sys/class/backlight/<backlight>/l1_daylight_max is defined 2 times: Documentation/ABI/testing/sysfs-class-backlight-adp8860:12 Documentation/ABI/testing/sysfs-class-backlight-driver-adp8870:4
Warning: /sys/class/leds/<led>/hw_pattern is defined 2 times: Documentation/ABI/testing/sysfs-class-led-trigger-pattern:14 Documentation/ABI/testing/sysfs-class-led-driver-sc27xx:0
Warning: /sys/class/leds/<led>/repeat is defined 2 times: Documentation/ABI/testing/sysfs-class-led-trigger-pattern:28 Documentation/ABI/testing/sysfs-class-led-driver-el15203000:0
Warning: /sys/kernel/iommu_groups/reserved_regions is defined 2 times: Documentation/ABI/testing/sysfs-kernel-iommu_groups:15 Documentation/ABI/testing/sysfs-kernel-iommu_groups:27

Right now, get_abi.pl has some logic to allow multiple "What:" with identical strings. It does that by adding extra random characters at the end of the reference name, and keeping track of them on some internal hash tables.

As the hash table is local to the script, an external script won't be able to handle it.

Once those gets fixed, we can consider moving the xref code to automarkup (although I suspect that this will be a way slower).

Thanks,
Mauro

I've gone ahead and applied the set, with the exception of #7 which doesn't apply here.

Thanks,

jon