support a pgx extension compiling with no_std (#385)

* support a pgx extension compiling with no_std

* fix some compilation issues

* cleanups

* support a pgx extension compiling with no_std

* fix some compilation issues

* cleanups

* fix compilation problem

.github/workflows/examples.yml

@@ -20,7 +20,7 @@ jobs:
       matrix:
         version: [10, 11, 12, 13, 14]
         os: ["ubuntu-latest"]
-        examples: ["aggregate", "arrays", "bad_ideas", "bgworker", "bytea", "custom_types",  "custom_sql", "errors", "operators", "schemas", "shmem", "spi", "srf", "strings", "triggers"]
+        examples: ["aggregate", "arrays", "bad_ideas", "bgworker", "bytea", "custom_types",  "custom_sql", "errors", "nostd", "operators", "schemas", "shmem", "spi", "srf", "strings", "triggers"]
 
     steps:
     - uses: actions/checkout@v2

Cargo.toml

@@ -26,6 +26,8 @@ exclude = [
     "pgx-examples/custom_types",
     "pgx-examples/custom_sql",
     "pgx-examples/errors",
+    "pgx-examples/nostd",
+    "pgx-examples/operators",
     "pgx-examples/schemas",
     "pgx-examples/shmem",
     "pgx-examples/spi",

pgx-examples/aggregate/src/lib.rs

@@ -1,7 +1,7 @@
-// use pgx::datum::sql_entity_graph::aggregate::{FinalizeModify, ParallelOption};
+use pgx::cstr_core::CStr;
 use pgx::*;
 use serde::{Deserialize, Serialize};
-use std::{ffi::CStr, str::FromStr};
+use std::str::FromStr;
 
 pg_module_magic!();
 
@@ -14,7 +14,10 @@ pub struct IntegerAvgState {
 
 impl IntegerAvgState {
     #[inline(always)]
-    fn state(mut current: <Self as Aggregate>::State, arg: <Self as Aggregate>::Args) -> <Self as Aggregate>::State {
+    fn state(
+        mut current: <Self as Aggregate>::State,
+        arg: <Self as Aggregate>::Args,
+    ) -> <Self as Aggregate>::State {
         current.sum += arg;
         current.n += 1;
         current
@@ -65,7 +68,11 @@ impl Aggregate for IntegerAvgState {
     const INITIAL_CONDITION: Option<&'static str> = Some("0,0");
 
     #[pgx(parallel_safe, immutable)]
-    fn state(current: Self::State, arg: Self::Args, _fcinfo: pg_sys::FunctionCallInfo) -> Self::State {
+    fn state(
+        current: Self::State,
+        arg: Self::Args,
+        _fcinfo: pg_sys::FunctionCallInfo,
+    ) -> Self::State {
         Self::state(current, arg)
     }
 
@@ -130,10 +137,7 @@ mod tests {
         let avg_state = IntegerAvgState::state(avg_state, 1);
         let avg_state = IntegerAvgState::state(avg_state, 2);
         let avg_state = IntegerAvgState::state(avg_state, 3);
-        assert_eq!(
-            2,
-            IntegerAvgState::finalize(avg_state),
-        );
+        assert_eq!(2, IntegerAvgState::finalize(avg_state),);
     }
 
     #[pg_test]

pgx-examples/custom_types/src/fixed_size.rs

@@ -1,5 +1,5 @@
+use pgx::cstr_core::CStr;
 use pgx::*;
-use std::ffi::CStr;
 use std::str::FromStr;
 
 #[derive(Copy, Clone, PostgresType)]

pgx-examples/nostd/.cargo/config

@@ -0,0 +1,16 @@
+# Auto-generated by pgx. You may edit this, or delete it to have a new one created.
+
+[target.x86_64-unknown-linux-gnu]
+linker = "./.cargo/pgx-linker-script.sh"
+
+[target.aarch64-unknown-linux-gnu]
+linker = "./.cargo/pgx-linker-script.sh"
+
+[target.x86_64-apple-darwin]
+linker = "./.cargo/pgx-linker-script.sh"
+
+[target.aarch64-apple-darwin]
+linker = "./.cargo/pgx-linker-script.sh"
+
+[target.x86_64-unknown-freebsd]
+linker = "./.cargo/pgx-linker-script.sh"

pgx-examples/nostd/.cargo/pgx-linker-script.sh

@@ -0,0 +1,19 @@
+#! /usr/bin/env bash
+# Auto-generated by pgx. You may edit this, or delete it to have a new one created.
+
+if [[ $CARGO_BIN_NAME == "sql-generator" ]]; then
+    UNAME=$(uname)
+    if [[ $UNAME == "Darwin" ]]; then
+        TEMP=$(mktemp pgx-XXX)
+        echo "*_pgx_internals_*" > ${TEMP}
+        gcc -exported_symbols_list ${TEMP} $@
+        rm -rf ${TEMP}
+    else
+        TEMP=$(mktemp pgx-XXX)
+        echo "{ __pgx_internals_*; };" > ${TEMP}
+        gcc -Wl,-dynamic-list=${TEMP} $@
+        rm -rf ${TEMP}
+    fi
+else
+    gcc -Wl,-undefined,dynamic_lookup $@
+fi

pgx-examples/nostd/.gitignore

@@ -0,0 +1,7 @@
+.DS_Store
+.idea/
+/target
+*.iml
+**/*.rs.bk
+Cargo.lock
+sql/nostd-1.0.sql

pgx-examples/nostd/Cargo.toml

@@ -0,0 +1,37 @@
+[package]
+name = "nostd"
+version = "0.0.0"
+edition = "2018"
+
+[lib]
+crate-type = ["cdylib", "rlib"]
+
+# remove this empty 'workspace' declaration if compiling outside of 'pgx'
+[workspace]
+
+[features]
+default = ["pg13"]
+pg10 = ["pgx/pg10", "pgx-tests/pg10" ]
+pg11 = ["pgx/pg11", "pgx-tests/pg11" ]
+pg12 = ["pgx/pg12", "pgx-tests/pg12" ]
+pg13 = ["pgx/pg13", "pgx-tests/pg13" ]
+pg14 = ["pgx/pg14", "pgx-tests/pg14" ]
+pg_test = []
+
+[dependencies]
+pgx = { path = "../../../pgx/pgx/", default-features = false }
+serde = "1.0.114"
+
+[dev-dependencies]
+pgx-tests = { path = "../../../pgx/pgx-tests" }
+
+# uncomment these if compiling outside of 'pgx'
+# [profile.dev]
+# panic = "unwind"
+# lto = "thin"
+
+# [profile.release]
+# panic = "unwind"
+# opt-level = 3
+# lto = "fat"
+# codegen-units = 1

pgx-examples/nostd/nostd.control

@@ -0,0 +1,5 @@
+comment = 'nostd:  Created by pgx'
+default_version = '1.0'
+module_pathname = '$libdir/nostd'
+relocatable = false
+superuser = false

pgx-examples/nostd/src/bin/sql-generator.rs

@@ -0,0 +1,2 @@
+/* Auto-generated by pgx. You may edit this, or delete it to have a new one created. */
+pgx::pg_binary_magic!(nostd);

pgx-examples/nostd/src/lib.rs

@@ -0,0 +1,51 @@
+//! This exists just to make sure we can compile various things under `#![no_std]`
+
+#![no_std]
+extern crate alloc;
+
+use pgx::*;
+use serde::{Deserialize, Serialize};
+
+use alloc::string::String;
+
+pg_module_magic!();
+
+/// standard Rust equality/comparison derives
+#[derive(Eq, PartialEq, Ord, Hash, PartialOrd)]
+
+/// Support using this struct as a Postgres type, which the easy way requires Serde
+#[derive(PostgresType, Serialize, Deserialize)]
+
+/// automatically generate =, <> SQL operator functions
+#[derive(PostgresEq)]
+
+/// automatically generate <, >, <=, >=, and a "_cmp" SQL functions
+/// When "PostgresEq" is also derived, pgx also creates an "opclass" (and family)
+/// so that the type can be used in indexes `USING btree`
+#[derive(PostgresOrd)]
+
+/// automatically generate a "_hash" function, and the necessary "opclass" (and family)
+/// so the type can also be used in indexes `USING hash`
+#[derive(PostgresHash)]
+pub struct Thing(String);
+
+#[derive(PostgresType, Serialize, Deserialize, Eq, PartialEq)]
+pub struct MyType {
+    value: i32,
+}
+
+#[pg_operator]
+#[opname(=)]
+fn my_eq(left: MyType, right: MyType) -> bool {
+    left == right
+}
+
+#[pg_extern]
+fn hello_nostd() -> &'static str {
+    "Hello, nostd"
+}
+
+#[pg_extern]
+fn echo(input: String) -> String {
+    input
+}

pgx-macros/src/lib.rs

@@ -294,12 +294,12 @@ extension_sql!(r#"\
 );
 
 #[pg_extern(immutable)]
-fn complex_in(input: &std::ffi::CStr) -> PgBox<Complex> {
+fn complex_in(input: &pgx::cstr_core::CStr) -> PgBox<Complex> {
     todo!()
 }
 
 #[pg_extern(immutable)]
-fn complex_out(complex: PgBox<Complex>) -> &'static std::ffi::CStr {
+fn complex_out(complex: PgBox<Complex>) -> &'static pgx::cstr_core::CStr {
     todo!()
 }
 
@@ -735,12 +735,12 @@ fn impl_postgres_type(ast: DeriveInput) -> proc_macro2::TokenStream {
             impl #generics JsonInOutFuncs #inout_generics for #name #generics {}
 
             #[pg_extern(immutable,parallel_safe)]
-            pub fn #funcname_in #generics(input: &#lifetime std::ffi::CStr) -> #name #generics {
+            pub fn #funcname_in #generics(input: &#lifetime pgx::cstr_core::CStr) -> #name #generics {
                 #name::input(input)
             }
 
             #[pg_extern(immutable,parallel_safe)]
-            pub fn #funcname_out #generics(input: #name #generics) -> &#lifetime std::ffi::CStr {
+            pub fn #funcname_out #generics(input: #name #generics) -> &#lifetime pgx::cstr_core::CStr {
                 let mut buffer = StringInfo::new();
                 input.output(&mut buffer);
                 buffer.into()
@@ -751,12 +751,12 @@ fn impl_postgres_type(ast: DeriveInput) -> proc_macro2::TokenStream {
         // otherwise if it's InOutFuncs our _in/_out functions use an owned type instance
         stream.extend(quote! {
             #[pg_extern(immutable,parallel_safe)]
-            pub fn #funcname_in #generics(input: &#lifetime std::ffi::CStr) -> #name #generics {
+            pub fn #funcname_in #generics(input: &#lifetime pgx::cstr_core::CStr) -> #name #generics {
                 #name::input(input)
             }
 
             #[pg_extern(immutable,parallel_safe)]
-            pub fn #funcname_out #generics(input: #name #generics) -> &#lifetime std::ffi::CStr {
+            pub fn #funcname_out #generics(input: #name #generics) -> &#lifetime pgx::cstr_core::CStr {
                 let mut buffer = StringInfo::new();
                 input.output(&mut buffer);
                 buffer.into()
@@ -766,12 +766,12 @@ fn impl_postgres_type(ast: DeriveInput) -> proc_macro2::TokenStream {
         // otherwise if it's PgVarlenaInOutFuncs our _in/_out functions use a PgVarlena
         stream.extend(quote! {
             #[pg_extern(immutable,parallel_safe)]
-            pub fn #funcname_in #generics(input: &#lifetime std::ffi::CStr) -> pgx::PgVarlena<#name #generics> {
+            pub fn #funcname_in #generics(input: &#lifetime pgx::cstr_core::CStr) -> pgx::PgVarlena<#name #generics> {
                 #name::input(input)
             }
 
             #[pg_extern(immutable,parallel_safe)]
-            pub fn #funcname_out #generics(input: pgx::PgVarlena<#name #generics>) -> &#lifetime std::ffi::CStr {
+            pub fn #funcname_out #generics(input: pgx::PgVarlena<#name #generics>) -> &#lifetime pgx::cstr_core::CStr {
                 let mut buffer = StringInfo::new();
                 input.output(&mut buffer);
                 buffer.into()

pgx-tests/src/tests/postgres_type_tests.rs

@@ -1,6 +1,6 @@
+use pgx::cstr_core::CStr;
 use pgx::*;
 use serde::{Deserialize, Serialize};
-use std::ffi::CStr;
 use std::str::FromStr;
 
 #[derive(Copy, Clone, PostgresType)]

pgx-utils/src/sql_entity_graph/extension_sql.rs

@@ -90,6 +90,9 @@ impl ToTokens for ExtensionSqlFile {
         let inv = quote! {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
                 let submission = pgx::datum::sql_entity_graph::ExtensionSqlEntity {
                     sql: include_str!(#path),
                     module_path: module_path!(),
@@ -194,6 +197,9 @@ impl ToTokens for ExtensionSql {
         let inv = quote! {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
                 let submission = pgx::datum::sql_entity_graph::ExtensionSqlEntity {
                     sql: #sql,
                     module_path: module_path!(),

pgx-utils/src/sql_entity_graph/pg_extern/mod.rs

@@ -229,6 +229,9 @@ impl ToTokens for PgExtern {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
                 use core::any::TypeId;
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
                 let submission = pgx::datum::sql_entity_graph::PgExternEntity {
                     name: #name,
                     unaliased_name: stringify!(#ident),

pgx-utils/src/sql_entity_graph/pg_schema.rs

@@ -64,7 +64,10 @@ impl ToTokens for Schema {
         updated_content.push(syn::parse_quote! {
                 #[no_mangle]
                 pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
-                    let submission = pgx::datum::sql_entity_graph::SchemaEntity {
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
+                let submission = pgx::datum::sql_entity_graph::SchemaEntity {
                         module_path: module_path!(),
                         name: stringify!(#ident),
                         file: file!(),

pgx-utils/src/sql_entity_graph/postgres_enum.rs

@@ -87,6 +87,9 @@ impl ToTokens for PostgresEnum {
         let inv = quote! {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
                 let mut mappings = Default::default();
                 <#name #ty_generics as pgx::datum::WithTypeIds>::register_with_refs(&mut mappings, stringify!(#name).to_string());
                 pgx::datum::WithSizedTypeIds::<#name #ty_generics>::register_sized_with_refs(&mut mappings, stringify!(#name).to_string());

pgx-utils/src/sql_entity_graph/postgres_hash.rs

@@ -86,6 +86,9 @@ impl ToTokens for PostgresHash {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
                 use core::any::TypeId;
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
                 let submission = pgx::datum::sql_entity_graph::PostgresHashEntity {
                     name: stringify!(#name),
                     file: file!(),

pgx-utils/src/sql_entity_graph/postgres_ord.rs

@@ -86,6 +86,9 @@ impl ToTokens for PostgresOrd {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
                 use core::any::TypeId;
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
                 let submission = pgx::datum::sql_entity_graph::PostgresOrdEntity {
                     name: stringify!(#name),
                     file: file!(),

pgx-utils/src/sql_entity_graph/postgres_type.rs

@@ -130,6 +130,11 @@ impl ToTokens for PostgresType {
         let inv = quote! {
             #[no_mangle]
             pub extern "C" fn  #sql_graph_entity_fn_name() -> pgx::datum::sql_entity_graph::SqlGraphEntity {
+                extern crate alloc;
+                use alloc::vec::Vec;
+                use alloc::vec;
+                use alloc::string::{String, ToString};
+
                 let mut mappings = Default::default();
                 <#name #ty_generics as pgx::datum::WithTypeIds>::register_with_refs(
                     &mut mappings,