info: use PNP ID database for manufacturer names

The three character PNP ID is a key to manufacturer name database. It
may be desirable to report the manufacturer's real name than just PNP ID
which can be misleading, e.g. MSI refers to Microstep and not MSI GmbH.

This builds the PNP ID database into libdisplay-info to avoid having to
find and parse files at runtime.

tool/gen-search-table.py started as a copy of Wayland 1.21.0's
src/embed.py and took influence from
10945c4ed8/conv.py
However, our script parses the text file shipped in hwdata package in
Debian (and presumably other distributions) rather than the original
CSV.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>

README.md

@@ -35,7 +35,12 @@ follows the [freedesktop.org Contributor Covenant].
 
 ## Building
 
-libdisplay-info is built using [Meson]. It has no dependencies.
+libdisplay-info has the following dependencies:
+
+- [hwdata](https://github.com/vcrhonek/hwdata) for the PNP ID database
+  used at build-time only.
+
+libdisplay-info is built using [Meson]:
 
     meson setup build/
     ninja -C build/

info.c

@@ -8,6 +8,10 @@
 #include "info.h"
 #include "log.h"
 
+/* Generated file pnp-id-table.c: */
+const char *
+pnp_id_table(const char *key);
+
 struct di_info *
 di_info_parse_edid(const void *data, size_t size)
 {
@@ -136,6 +140,7 @@ di_info_get_make(const struct di_info *info)
 {
 	const struct di_edid_vendor_product *evp;
 	char pnp_id[(sizeof(evp->manufacturer)) + 1] = { 0, };
+	const char *manuf;
 	struct memory_stream m;
 
 	if (!info->edid)
@@ -147,7 +152,11 @@ di_info_get_make(const struct di_info *info)
 	evp = di_edid_get_vendor_product(info->edid);
 	memcpy(pnp_id, evp->manufacturer, sizeof(evp->manufacturer));
 
-	/* TODO: use pnp.ids to convert to a company name */
+	manuf = pnp_id_table(pnp_id);
+	if (manuf) {
+		encode_ascii_string(m.fp, manuf);
+		return memory_stream_close(&m);
+	}
 
 	fputs("PNP(", m.fp);
 	encode_ascii_string(m.fp, pnp_id);

meson.build

@@ -10,6 +10,21 @@ project(
 	],
 )
 
+dep_hwdata = dependency('hwdata', required: false, native: true)
+if dep_hwdata.found()
+	hwdata_dir = dep_hwdata.get_variable(pkgconfig: 'pkgdatadir')
+	pnp_ids = files(hwdata_dir / 'pnp.ids')
+else
+	pnp_ids = files('/usr/share/hwdata/pnp.ids')
+endif
+
+gen_search_table = find_program('tool/gen-search-table.py')
+pnp_id_table = custom_target(
+	'pnp-id-table.c',
+	command: [ gen_search_table, pnp_ids, '@OUTPUT@', 'pnp_id_table' ],
+	output: 'pnp-id-table.c',
+)
+
 cc = meson.get_compiler('c')
 
 math = cc.find_library('m', required: false)
@@ -42,6 +57,7 @@ di_lib = library(
 		'gtf.c',
 		'info.c',
 		'log.c',
+		pnp_id_table,
 	],
 	include_directories: include_directories('include'),
 	dependencies: [math],

test/data/acer-p1276.print

@@ -1,3 +1,3 @@
-make: PNP(ACR)
+make: Acer Technologies
 model: P1276
 serial: JGG110015900

test/data/apple-xdr-dp.print

@@ -1,3 +1,3 @@
-make: PNP(APP)
+make: Apple Computer Inc
 model: ProDisplayXDR
 serial: 0x250D0E02

test/data/custom-uncommon-cta-vesa.print

@@ -1,3 +1,3 @@
-make: PNP(LNX)
+make: The Linux Foundation
 model: hdmi-4k-600
 serial: {null}

test/data/dell-2408wfp-dp.print

@@ -1,3 +1,3 @@
-make: PNP(DEL)
+make: Dell Inc.
 model: DELL 2408WFP
 serial: G283H8BI21MS

test/data/goldstar-ite6604-hdmi.print

@@ -1,3 +1,3 @@
-make: PNP(GSM)
+make: LG Electronics
 model: ITE6604
 serial: 0x01010101

test/data/hp-5dq99aa-hdmi.print

@@ -1,3 +1,3 @@
-make: PNP(HPN)
+make: HP Inc.
 model: HP 27 QD
 serial: CN49120J6N

test/data/msi-mag321curv-dp.print

@@ -1,3 +1,3 @@
-make: PNP(MSI)
+make: Microstep
 model: MAG321CURV
 serial: DA2A019360041

test/data/panasonic-mei96a2-dp.print

@@ -1,3 +1,3 @@
-make: PNP(MEI)
+make: Panasonic Industry Company
 model: 0x96A2
 serial: {null}

test/data/samsung-s27a950d-dp.print

@@ -1,3 +1,3 @@
-make: PNP(SAM)
+make: Samsung Electric Company
 model: S27A950D
 serial: {null}

test/data/sun-gh19ps-dvi.print

@@ -1,3 +1,3 @@
-make: PNP(SUN)
+make: Sun Electronics Corporation
 model: GH19PS
 serial: 0432MR0406

test/data/viewsonic-vp2768-dp.print

@@ -1,3 +1,3 @@
-make: PNP(VSC)
+make: ViewSonic Corporation
 model: VP2768 Series
 serial: UY5171500307

tool/gen-search-table.py

@@ -0,0 +1,91 @@
+#!/usr/bin/env python3
+
+"""
+string to string mapping table
+
+License: MIT
+
+Copyright (c) 2020 Simon Ser
+Copyright 2022 Collabora, Ltd.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+"""
+
+import sys
+
+def escape_for_c(s):
+    l = [c if c.isalnum() or c in ' .,' else '\\%03o' % ord(c) for c in s]
+    return ''.join(l)
+
+if len(sys.argv) != 4:
+    print('usage: ' + sys.argv[0] + ' <infile> <outfile> <ident>', file=sys.stderr)
+    sys.exit(1)
+
+infile = sys.argv[1]
+outfile = sys.argv[2]
+ident = sys.argv[3]
+
+records = {}
+
+with open(infile, 'r') as f:
+    for line in f:
+        [pnpid, name] = line.split(maxsplit=1)
+
+        if len(pnpid) != 3:
+            print("Warning: skipping invalid PNP ID %s" % (repr(pnpid)), file=sys.stderr)
+            continue
+
+        records[pnpid] = escape_for_c(name.strip())
+
+with open(outfile, 'w') as f:
+    f.write(
+f'''
+#include <string.h>
+#include <stdint.h>
+
+const char *
+{ident}(const char *key);
+
+const char *
+{ident}(const char *key)
+{{
+    size_t len = strlen(key);
+    size_t i;
+    uint32_t u = 0;
+
+    if (len > 4)
+        return NULL;
+
+    for (i = 0; i < len; i++)
+        u = (u << 8) | (uint8_t)key[i];
+
+    switch (u) {{
+''')
+    for id in sorted(records.keys()):
+        u = 0
+        for c in id:
+            u = (u << 8) | ord(c)
+        f.write(f'    case {u}: return "{records[id]}";\n')
+    f.write(
+f'''
+    default:
+        return NULL;
+    }}
+}}
+''')