From 5c3bbdf1147e1097d4543216c18b1642839214d1 Mon Sep 17 00:00:00 2001
From: Hayodea Hakol <hayodea@protonmail.com>
Date: Tue, 7 Jan 2025 14:08:17 -0400
Subject: [PATCH] Devspec: Add lexer and parser for devSpecs

This grammar looks simple but it consumed 2 days of my time
and it's giving me bugs all the same, but mostly working
nicely.

See the syntax documentation in /docs
---
 hcore/deviceManager/Makefile.am    |  16 +++-
 hcore/deviceManager/deviceSpecl.ll |  34 +++++++++
 hcore/deviceManager/deviceSpecp.yy | 118 +++++++++++++++++++++++++++++
 3 files changed, 167 insertions(+), 1 deletion(-)
 create mode 100644 hcore/deviceManager/deviceSpecl.ll
 create mode 100644 hcore/deviceManager/deviceSpecp.yy

diff --git a/hcore/deviceManager/Makefile.am b/hcore/deviceManager/Makefile.am
index bc5f355..65a6ca3 100644
--- a/hcore/deviceManager/Makefile.am
+++ b/hcore/deviceManager/Makefile.am
@@ -1,4 +1,18 @@
 AM_CPPFLAGS+= -I"$(top_srcdir)/hcore/include"
+AM_YFLAGS = -d
 
 noinst_LIBRARIES = libdeviceManager.a
-libdeviceManager_a_SOURCES = deviceManager.cpp deviceSpecParser.cpp
+libdeviceManager_a_SOURCES = deviceSpecp.yy deviceSpecl.ll \
+    deviceManager.cpp deviceSpecParser.cpp
+
+deviceSpecl.cc: deviceSpecl.ll
+deviceSpecl.o: AM_LFLAGS += --header-file=deviceSpecl.hh \
+    -o deviceSpecl.cc
+deviceSpecp.cc deviceSpecp.hh: deviceSpecp.yy
+deviceSpecp.o: AM_YFLAGS += -p deviceSpecp \
+    --header=deviceSpecp.hh -o deviceSpecp.cc
+
+deviceSpecParser.o: AM_CXXFLAGS+=-Wno-ignored-attributes
+
+CLEANFILES=deviceSpecp.cc deviceSpecp.hh \
+    deviceSpecl.cc deviceSpecl.hh
diff --git a/hcore/deviceManager/deviceSpecl.ll b/hcore/deviceManager/deviceSpecl.ll
new file mode 100644
index 0000000..0187e07
--- /dev/null
+++ b/hcore/deviceManager/deviceSpecl.ll
@@ -0,0 +1,34 @@
+%option prefix="deviceSpecl"
+%{
+#include <vector>
+#include <deviceManager/deviceManager.h>
+#include "deviceSpecp.hh"
+%}
+
+%%
+^a              {
+                    deviceSpecplval.chr = yytext[0];
+                    return KEYWORD_SPECTYPE_ACTUATOR;
+                }
+^e              {
+                    deviceSpecplval.chr = yytext[0];
+                    return KEYWORD_SPECTYPE_EXTROSPECTOR;
+                }
+^i              {
+                    deviceSpecplval.chr = yytext[0];
+                    return KEYWORD_SPECTYPE_INTEROSPECTOR;
+                }
+"||"            { return DOUBLE_PIPE; }
+"|"             { return PIPE; }
+"("             { return LPAREN; }
+")"             { return RPAREN; }
+[^\|\(\) \t\r\n]+ { deviceSpecplval.str = strdup(yytext); return STRING; }
+\r?\n           { /* ignore newlines */ }
+[ \t]+          { /* ignore whitespace */ }
+.               { return yytext[0]; }
+%%
+
+int deviceSpeclwrap(void)
+{
+    return 1; // Indicate end of input
+}
diff --git a/hcore/deviceManager/deviceSpecp.yy b/hcore/deviceManager/deviceSpecp.yy
new file mode 100644
index 0000000..e1e867b
--- /dev/null
+++ b/hcore/deviceManager/deviceSpecp.yy
@@ -0,0 +1,118 @@
+%{
+#include <vector>
+#include <utility>
+#include <string>
+#include <cstring>
+#include <cstdlib>
+#include <stdexcept>
+#include <deviceManager/deviceManager.h>
+
+#ifndef yylex
+/* We use different prefixes for the lexer and parser.
+ * * Our lexer's prefix is deviceSpecl.
+ * * Our parser's prefix is deviceSpecp.
+ *
+ * Yacc and Bison don't have a way to handle the scenario where the lexer has
+ * a different prefix from the parser that they generate. They assume that the
+ * lexer must have the same prefix as the parser they generate. So we just use
+ * this #define below to override yacc/bison's presumed prefix for the lexer.
+ */
+#error "Yacc should have defined yylex, and we need to override it to tell yacc the name of our lex function."
+#endif
+#undef yylex
+#define yylex deviceSpecllex
+
+// Declare the symbols that our lexer will export.
+int yylex(void);
+void yyerror(const char *message)
+{
+	throw std::runtime_error(
+        std::string("deviceSpec parser error: ")
+            + std::string(message)) + yytext;
+}
+
+%}
+
+%union {
+    char* str;
+    char chr;
+    DeviceManager::SensorDeviceSpec* sensorSpec;
+    DeviceManager::InteroceptorDeviceSpec* interoceptorSpec;
+    DeviceManager::ExtrospectorDeviceSpec* extrospectorSpec;
+    std::vector<std::string>* stringVector;
+}
+
+%token <str> STRING
+%token PIPE DOUBLE_PIPE LPAREN RPAREN
+%token <chr> KEYWORD_SPECTYPE_ACTUATOR
+%token <chr> KEYWORD_SPECTYPE_EXTROSPECTOR KEYWORD_SPECTYPE_INTEROSPECTOR
+
+%type <stringVector> params opt_params
+%type <sensorSpec> spec_body
+%type <interoceptorSpec> interoceptor_spec
+%type <extrospectorSpec> extrospector_spec
+
+%%
+
+file: /* NOTHING */
+    | sensor_specs
+    ;
+
+sensor_specs:
+    sensor_spec
+    | sensor_specs DOUBLE_PIPE sensor_spec
+    ;
+
+sensor_spec:
+    interoceptor_spec
+    | extrospector_spec
+    ;
+
+interoceptor_spec:
+    KEYWORD_SPECTYPE_INTEROSPECTOR PIPE spec_body {
+        DeviceManager::InteroceptorDeviceSpec *spec =
+            static_cast<DeviceManager::InteroceptorDeviceSpec *>($3);
+
+        spec->sensorType = $1;
+        DeviceManager::interoceptorDeviceSpecs.push_back(*spec);
+        delete spec;
+    }
+    ;
+
+extrospector_spec:
+    KEYWORD_SPECTYPE_EXTROSPECTOR PIPE spec_body {
+        DeviceManager::ExtrospectorDeviceSpec *spec =
+            static_cast<DeviceManager::ExtrospectorDeviceSpec *>($3);
+
+        spec->sensorType = $1;
+        DeviceManager::extrospectorDeviceSpecs.push_back(*spec);
+        delete spec;
+    }
+    ;
+
+spec_body:
+    STRING PIPE STRING LPAREN opt_params RPAREN PIPE STRING LPAREN opt_params RPAREN PIPE STRING {
+        $$ = new DeviceManager::SensorDeviceSpec();
+        $$->sensorType = '\0';
+        $$->implexor = std::string($1);
+        $$->api = std::string($3);
+        $$->apiParams = std::move(*$5);
+        $$->server = std::string($8);
+        $$->serverParams = std::move(*$10);
+        $$->deviceSelector = std::string($13);
+        delete $5;
+        delete $10;
+    }
+    ;
+
+opt_params:
+    params
+    | /* empty */ { $$ = new std::vector<std::string>(); }
+    ;
+
+params:
+    STRING { $$ = new std::vector<std::string>{ $1 }; }
+    | params PIPE STRING { $$ = $1; $$->push_back($3); }
+    ;
+
+%%