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Merged
treeform merged 1 commit into from
May 25, 2026
Merged

Fix string memory ownership issues with GennyBuffer. #66

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39 changes: 30 additions & 9 deletions src/genny/internal.nim
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -47,7 +47,7 @@ proc exportProcInternal*(
internal.removeSuffix ", "
internal.add ")"
if procReturn.kind != nnkEmpty:
internal.add &": {exportTypeNim(procReturn)}"
internal.add &": {exportReturnTypeNim(procReturn)}"
internal.add &" {exportProcPragmas} =\n"
if procRaises:
internal.add " try:\n "
Expand All @@ -68,7 +68,7 @@ proc exportProcInternal*(
if procReturnsSeq:
internal.add &"{procReturn.getSeqName()}(s: {callExpr})"
elif procReturn.kind != nnkEmpty:
internal.add convertExportExprNim(callExpr, procReturn)
internal.add convertExportReturnExprNim(callExpr, procReturn)
else:
internal.add callExpr
if procRaises:
Expand Down Expand Up @@ -155,10 +155,10 @@ proc exportRefObjectInternal*(
if fieldType.kind != nnkBracketExpr:
internal.add "proc "
internal.add &"$lib_{objNameSnaked}_get_{fieldNameSnaked}*"
internal.add &"({objNameSnaked}: {objName}): {exportTypeNim(fieldType)}"
internal.add &"({objNameSnaked}: {objName}): {exportReturnTypeNim(fieldType)}"
internal.add &" {exportProcPragmas} =\n"
internal.add " "
internal.add convertExportExprNim(&"{objNameSnaked}.{fieldName}", fieldType)
internal.add convertExportReturnExprNim(&"{objNameSnaked}.{fieldName}", fieldType)
internal.add "\n"
internal.add "\n"

Expand Down Expand Up @@ -186,10 +186,10 @@ proc exportRefObjectInternal*(
internal.add ")\n"
internal.add "\n"

internal.add &"proc {prefix}_get*({objNameSnaked}: {objName}, i: int): {exportTypeNim(fieldType[1])}"
internal.add &"proc {prefix}_get*({objNameSnaked}: {objName}, i: int): {exportReturnTypeNim(fieldType[1])}"
internal.add &" {exportProcPragmas} =\n"
internal.add " "
internal.add convertExportExprNim(&"{objNameSnaked}.{fieldName}[i]", fieldType[1])
internal.add convertExportReturnExprNim(&"{objNameSnaked}.{fieldName}[i]", fieldType[1])
internal.add "\n"
internal.add "\n"

Expand Down Expand Up @@ -240,11 +240,11 @@ proc generateSeqs(sym: NimNode) =
internal.add ")\n"
internal.add "\n"

internal.add &"proc $lib_{seqNameSnaked}_get*(s: {seqName}, i: int): {exportTypeNim(sym[1])}"
internal.add &"proc $lib_{seqNameSnaked}_get*(s: {seqName}, i: int): {exportReturnTypeNim(sym[1])}"
internal.add &" {exportProcPragmas}"
internal.add " =\n"
internal.add " "
internal.add convertExportExprNim("s.s[i]", sym[1])
internal.add convertExportReturnExprNim("s.s[i]", sym[1])
internal.add "\n"
internal.add "\n"

Expand Down Expand Up @@ -283,11 +283,32 @@ when not defined(gcArc) and not defined(gcOrc):

when (NimMajor, NimMinor, NimPatch) == (1, 6, 2):
{.error: "Nim 1.6.2 not supported with Genny due to FFI issues.".}

type GennyBuffer* = ref object
data: string

proc newGennyBuffer*(data: string): GennyBuffer =
result = GennyBuffer(data: data)
GC_ref(result)

proc $lib_genny_buffer_data*(buffer: GennyBuffer): cstring {.raises: [], cdecl, exportc, dynlib.} =
if buffer == nil:
return nil
buffer.data.cstring

proc $lib_genny_buffer_len*(buffer: GennyBuffer): int {.raises: [], cdecl, exportc, dynlib.} =
if buffer == nil:
return 0
buffer.data.len

proc $lib_genny_buffer_unref*(buffer: GennyBuffer) {.raises: [], cdecl, exportc, dynlib.} =
if buffer != nil:
GC_unref(buffer)
"""

proc writeInternal*(dir, lib: string) =
createDir(dir)
writeFile(
&"{dir}/internal.nim",
header & internal.replace("$Lib", lib).replace("$lib", toSnakeCase(lib))
(header & internal).replace("$Lib", lib).replace("$lib", toSnakeCase(lib))
)
23 changes: 19 additions & 4 deletions src/genny/languages/c.nim
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -55,6 +55,13 @@ proc exportTypeC(sym: NimNode): string =
else:
typ.repr

proc exportReturnTypeC(sym: NimNode): string =
let typ = sym.stripSink
if typ.repr == "string":
"GennyBuffer"
else:
exportTypeC(typ)

proc exportTypeC(sym: NimNode, name: string): string =
let typ = sym.stripSink
if typ.kind == nnkBracketExpr:
Expand Down Expand Up @@ -142,7 +149,7 @@ proc exportProcC*(
var dllParams: seq[(NimNode, NimNode)]
for param in procParams:
dllParams.add((param[0], param[1]))
dllProc(&"$lib_{apiProcName}", dllParams, exportTypeC(procReturn))
dllProc(&"$lib_{apiProcName}", dllParams, exportReturnTypeC(procReturn))

proc exportObjectC*(sym: NimNode, constructor: NimNode) =
let objName = sym.repr
Expand Down Expand Up @@ -175,7 +182,7 @@ proc genRefObject(objName: string) =
proc genSeqProcs(objName, procPrefix, selfSuffix: string, entryType: NimNode) =
let objArg = objName & " " & toSnakeCase(objName)
dllProc(&"{procPrefix}_len", [objArg], "intptr_t")
dllProc(&"{procPrefix}_get", [objArg, "intptr_t index"], exportTypeC(entryType))
dllProc(&"{procPrefix}_get", [objArg, "intptr_t index"], exportReturnTypeC(entryType))
dllProc(&"{procPrefix}_set", [objArg, "intptr_t index", exportTypeC(entryType, "value")], "void")
dllProc(&"{procPrefix}_delete", [objArg, "intptr_t index"], "void")
dllProc(&"{procPrefix}_add", [objArg, exportTypeC(entryType, "value")], "void")
Expand Down Expand Up @@ -213,7 +220,7 @@ proc exportRefObjectC*(

let setProcName = &"$lib_{objNameSnaked}_set_{fieldNameSnaked}"

dllProc(getProcName, [objName & " " & objNameSnaked], exportTypeC(fieldType))
dllProc(getProcName, [objName & " " & objNameSnaked], exportReturnTypeC(fieldType))
dllProc(setProcName, [objName & " " & objNameSnaked, exportTypeC(fieldType, "value")], exportTypeC(nil))
else:
var helperName = fieldName
Expand Down Expand Up @@ -251,6 +258,14 @@ const header = """

#include <stdint.h>

typedef struct GennyBufferHandle* GennyBuffer;

"""

const bufferProcs = """
const char* $lib_genny_buffer_data(GennyBuffer buffer);
intptr_t $lib_genny_buffer_len(GennyBuffer buffer);
void $lib_genny_buffer_unref(GennyBuffer buffer);
"""

const externCStart = """
Expand All @@ -273,6 +288,6 @@ const footer = """

proc writeC*(dir, lib: string) =
createDir(dir)
writeFile(&"{dir}/{toSnakeCase(lib)}.h", (header & types & externCStart & procs & externCEnd & footer)
writeFile(&"{dir}/{toSnakeCase(lib)}.h", (header & types & externCStart & bufferProcs & procs & externCEnd & footer)
.replace("$lib", toSnakeCase(lib)).replace("$LIB", lib.toUpperAscii())
)
104 changes: 89 additions & 15 deletions src/genny/languages/cpp.nim
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,6 +24,9 @@ proc isSeqLike(sym: NimNode): bool =
proc isRuneType(sym: NimNode): bool =
sym.stripSink.repr == "Rune"

proc isStringType(sym: NimNode): bool =
sym.stripSink.repr == "string"

proc exportTypeCpp(sym: NimNode, abi = false): string =
let typ = sym.stripSink
if typ.kind == nnkBracketExpr:
Expand Down Expand Up @@ -70,6 +73,18 @@ proc exportTypeCpp(sym: NimNode, abi = false): string =
proc exportTypeCppAbi(sym: NimNode): string =
exportTypeCpp(sym, abi = true)

proc exportReturnTypeCpp(sym: NimNode): string =
if sym.isStringType:
"std::string"
else:
exportTypeCpp(sym)

proc exportReturnTypeCppAbi(sym: NimNode): string =
if sym.isStringType:
"GennyBuffer"
else:
exportTypeCppAbi(sym)

proc exportTypeCpp(sym: NimNode, name: string, abi = false): string =
let typ = sym.stripSink
if typ.kind == nnkBracketExpr:
Expand All @@ -95,7 +110,9 @@ proc cppArgValue(argType: NimNode, argName: string): string =
argName

proc cppReturnValue(returnType: NimNode, call: string): string =
if returnType.isRuneType:
if returnType.isStringType:
&"gennyBufferToString({call})"
elif returnType.isRuneType:
&"static_cast<char32_t>({call})"
else:
call
Expand Down Expand Up @@ -156,11 +173,11 @@ proc exportProcCpp*(
var dllParams: seq[(NimNode, NimNode)]
for param in procParams:
dllParams.add((param[0], param[1]))
dllProc(&"$lib_{apiProcName}", dllParams, exportTypeCppAbi(procReturn))
dllProc(&"$lib_{apiProcName}", dllParams, exportReturnTypeCppAbi(procReturn))

if owner == nil:
if procReturn.kind != nnkEmpty:
members.add exportTypeCpp(procReturn)
members.add exportReturnTypeCpp(procReturn)
members.add " "
members.add procName
members.add "("
Expand Down Expand Up @@ -199,14 +216,14 @@ proc exportProcCpp*(
classes.add &" * {line}\n"
classes.add " */\n"

classes.add &" {exportTypeCpp(procReturn)} {procName}("
classes.add &" {exportReturnTypeCpp(procReturn)} {procName}("
for param in procParams[1..^1]:
classes.add exportTypeCpp(param[1], param[0].getName())
classes.add ", "
classes.removeSuffix ", "
classes.add ");\n\n"

members.add &"{exportTypeCpp(procReturn)} {owner.getName()}::{procName}("
members.add &"{exportReturnTypeCpp(procReturn)} {owner.getName()}::{procName}("
for param in procParams[1..^1]:
members.add exportTypeCpp(param[1], param[0].getName())
members.add ", "
Expand Down Expand Up @@ -278,7 +295,7 @@ proc genRefObject(objName: string) =
proc genSeqProcs(objName, procPrefix, selfSuffix: string, entryType: NimNode) =
let objArg = objName & " " & toSnakeCase(objName)
dllProc(&"{procPrefix}_len", [objArg], "std::intptr_t")
dllProc(&"{procPrefix}_get", [objArg, "std::intptr_t index"], exportTypeCppAbi(entryType))
dllProc(&"{procPrefix}_get", [objArg, "std::intptr_t index"], exportReturnTypeCppAbi(entryType))
dllProc(&"{procPrefix}_set", [objArg, "std::intptr_t index", exportTypeCppAbi(entryType, "value")], "void")
dllProc(&"{procPrefix}_delete", [objArg, "std::intptr_t index"], "void")
dllProc(&"{procPrefix}_add", [objArg, exportTypeCppAbi(entryType, "value")], "void")
Expand All @@ -287,12 +304,13 @@ proc genSeqProcs(objName, procPrefix, selfSuffix: string, entryType: NimNode) =
proc genSeqClassMethods(seqName, procPrefix: string, entryType: NimNode) =
let
entryTypeCpp = exportTypeCpp(entryType)
entryReturnTypeCpp = exportReturnTypeCpp(entryType)
entryValue = cppArgValue(entryType, "value")
getCall = &"{procPrefix}_get(*this, index)"

classes.add &" std::intptr_t size();\n"
classes.add &" {entryTypeCpp} get(std::intptr_t index);\n"
classes.add &" {entryTypeCpp} operator[](std::intptr_t index);\n"
classes.add &" {entryReturnTypeCpp} get(std::intptr_t index);\n"
classes.add &" {entryReturnTypeCpp} operator[](std::intptr_t index);\n"
classes.add &" void set(std::intptr_t index, {entryTypeCpp} value);\n"
classes.add &" void removeAt(std::intptr_t index);\n"
classes.add &" void add({entryTypeCpp} value);\n"
Expand All @@ -302,11 +320,11 @@ proc genSeqClassMethods(seqName, procPrefix: string, entryType: NimNode) =
members.add &" return {procPrefix}_len(*this);\n"
members.add "}\n\n"

members.add &"{entryTypeCpp} {seqName}::get(std::intptr_t index)" & "{\n"
members.add &"{entryReturnTypeCpp} {seqName}::get(std::intptr_t index)" & "{\n"
members.add &" return {cppReturnValue(entryType, getCall)};\n"
members.add "}\n\n"

members.add &"{entryTypeCpp} {seqName}::operator[](std::intptr_t index)" & "{\n"
members.add &"{entryReturnTypeCpp} {seqName}::operator[](std::intptr_t index)" & "{\n"
members.add &" return get(index);\n"
members.add "}\n\n"

Expand All @@ -332,11 +350,12 @@ proc genSeqFieldMethods(objName, procPrefix, fieldName: string, entryType: NimNo

let
entryTypeCpp = exportTypeCpp(entryType)
entryReturnTypeCpp = exportReturnTypeCpp(entryType)
entryValue = cppArgValue(entryType, "value")
getCall = &"{procPrefix}_get(*this, index)"

classes.add &" std::intptr_t {fieldName}Size();\n"
classes.add &" {entryTypeCpp} get{fieldCap}(std::intptr_t index);\n"
classes.add &" {entryReturnTypeCpp} get{fieldCap}(std::intptr_t index);\n"
classes.add &" void set{fieldCap}(std::intptr_t index, {entryTypeCpp} value);\n"
classes.add &" void remove{fieldCap}(std::intptr_t index);\n"
classes.add &" void add{fieldCap}({entryTypeCpp} value);\n"
Expand All @@ -346,7 +365,7 @@ proc genSeqFieldMethods(objName, procPrefix, fieldName: string, entryType: NimNo
members.add &" return {procPrefix}_len(*this);\n"
members.add "}\n\n"

members.add &"{entryTypeCpp} {objName}::get{fieldCap}(std::intptr_t index)" & "{\n"
members.add &"{entryReturnTypeCpp} {objName}::get{fieldCap}(std::intptr_t index)" & "{\n"
members.add &" return {cppReturnValue(entryType, getCall)};\n"
members.add "}\n\n"

Expand Down Expand Up @@ -428,12 +447,12 @@ proc exportRefObjectCpp*(
let getMemberName = &"get{fieldName.capitalizeAscii}"
let setMemberName = &"set{fieldName.capitalizeAscii}"

dllProc(getProcName, [objName & " " & objNameSnaked], exportTypeCppAbi(fieldType))
dllProc(getProcName, [objName & " " & objNameSnaked], exportReturnTypeCppAbi(fieldType))
dllProc(setProcName, [objName & " " & objNameSnaked, exportTypeCppAbi(fieldType, "value")], exportTypeCppAbi(nil))

classes.add &" {exportTypeCpp(fieldType)} {getMemberName}();\n"
classes.add &" {exportReturnTypeCpp(fieldType)} {getMemberName}();\n"

members.add &"{exportTypeCpp(fieldType)} {objName}::{getMemberName}()" & "{\n"
members.add &"{exportReturnTypeCpp(fieldType)} {objName}::{getMemberName}()" & "{\n"
let getCall = &"{getProcName}(*this)"
members.add &" return {cppReturnValue(fieldType, getCall)};\n"
members.add "}\n\n"
Expand Down Expand Up @@ -529,7 +548,59 @@ const header = """
#ifndef INCLUDE_$LIB_H
#define INCLUDE_$LIB_H

#include <cstddef>
#include <cstdint>
#include <string>

"""

const bufferClass = """
struct GennyBuffer {

private:

std::uintptr_t reference;

public:

const char* data();
std::intptr_t len();
void free();

};

"""

const bufferProcs = """
const char* $lib_genny_buffer_data(GennyBuffer buffer);
std::intptr_t $lib_genny_buffer_len(GennyBuffer buffer);
void $lib_genny_buffer_unref(GennyBuffer buffer);

"""

const bufferMembers = """
static inline std::string gennyBufferToString(GennyBuffer buffer) {
const char* data = $lib_genny_buffer_data(buffer);
std::intptr_t len = $lib_genny_buffer_len(buffer);
std::string result;
if (data != nullptr && len > 0) {
result.assign(data, static_cast<std::size_t>(len));
}
$lib_genny_buffer_unref(buffer);
return result;
}

const char* GennyBuffer::data() {
return $lib_genny_buffer_data(*this);
}

std::intptr_t GennyBuffer::len() {
return $lib_genny_buffer_len(*this);
}

void GennyBuffer::free() {
$lib_genny_buffer_unref(*this);
}

"""

Expand All @@ -542,10 +613,13 @@ proc writeCpp*(dir, lib: string) =
writeFile(&"{dir}/{toSnakeCase(lib)}.hpp", (
header &
types &
bufferClass &
classes &
"extern \"C\" {\n\n" &
bufferProcs &
procs &
"}\n\n" &
bufferMembers &
members &
footer
).replace("$lib", toSnakeCase(lib)).replace("$LIB", lib.toUpperAscii())
Expand Down
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