ironwork_rt/lir/
sql.rs

1//! EXEC SQL (lir.md §9.7): the program's statement table, which the SQL runtime reads. WHENEVER is
2//! not in it: lowering emits it as `Cond::Sql` branches after the op.
3
4use super::{AbendId, PlaceId, SymId};
5use crate::sql::{HostType, fingerprint};
6use crate::{codec_enum, codec_struct};
7
8/// One EXEC SQL block, declarative ones included; `Program.sql[k − 1]` has ordinal k. `P` and `S`
9/// are the executor's handles to a data item and to text: the LIR's ids by default, the walker's
10/// own references in the interpreter.
11#[derive(Clone, Debug, PartialEq, Eq)]
12pub struct SqlEntry<P = PlaceId, S = SymId> {
13    pub ordinal: u32,
14    /// The command word the call record and the EXEC messages name.
15    pub verb: S,
16    pub statement: SqlStatement<P, S>,
17    /// What a `Database` call receives, `?` for each input; empty for a declaration. A dynamic
18    /// statement's call sends its statement string instead, and this names the statement.
19    pub text: S,
20    pub fingerprint: u32,
21    /// Set on the OPEN of a cursor declared WITH HOLD, and on no other entry.
22    pub with_hold: bool,
23}
24
25/// The typed statement with its host variables resolved and each OPEN given its DECLARE's inputs.
26#[derive(Clone, Debug, PartialEq, Eq)]
27pub enum SqlStatement<P = PlaceId, S = SymId> {
28    Query { inputs: Vec<HostPlace<P>>, into: Vec<HostPlace<P>> },
29    Change { delete: bool, inputs: Vec<HostPlace<P>>, current_of: Option<S> },
30    Open { cursor: S, inputs: Vec<HostPlace<P>> },
31    Fetch { cursor: S, into: Vec<HostPlace<P>> },
32    Close { cursor: S },
33    Commit,
34    Rollback,
35    /// PREPARE of the statement `name` from the statement string in `source`, which must be one
36    /// varying-length character or graphic string.
37    Prepare { name: S, source: Vec<HostPlace<P>> },
38    ExecuteImmediate { source: Vec<HostPlace<P>> },
39    /// EXECUTE of a prepared statement, `inputs` replacing its parameter markers.
40    Execute { name: S, inputs: Vec<HostPlace<P>> },
41    /// OPEN of a cursor declared for the prepared statement `statement`.
42    OpenPrepared { cursor: S, statement: S, inputs: Vec<HostPlace<P>> },
43    /// WHENEVER, DECLARE CURSOR, INCLUDE and the other declarations: no op.
44    Declaration,
45    /// Abends EXEC, naming it, when reached.
46    Unsupported(S),
47    /// CONNECT or SET CONNECTION: the host variable naming the location, if any, goes to the
48    /// input trace, then the statement abends EXEC as an unsupported one does.
49    Connect { what: S, location: Vec<HostPlace<P>> },
50}
51
52/// A host variable, or one member of a host structure at `member`'s offset and length. The
53/// indicator comes with the offset of this member's element in it.
54#[derive(Clone, Debug, PartialEq, Eq)]
55pub struct HostPlace<P = PlaceId> {
56    pub var: P,
57    pub member: Option<(u32, u32)>,
58    /// Never a structure. An item with no SQL type keeps the walker's EXEC abend.
59    pub ty: Result<HostType, AbendId>,
60    pub indicator: Option<(P, u32)>,
61}
62
63/// The SQLCA fields the program declares, or its own SQLCODE and SQLSTATE, in the order filled.
64#[derive(Clone, Debug, Default, PartialEq, Eq)]
65pub struct Sqlca<P = PlaceId> {
66    pub fields: Vec<(SqlcaField, P, HostType)>,
67}
68
69#[derive(Clone, Copy, Debug, PartialEq, Eq)]
70pub enum SqlcaField {
71    CaId,
72    CaBc,
73    Code,
74    ErrMl,
75    ErrMc,
76    ErrP,
77    State,
78    /// SQLERRD(n), n from 1 to 6.
79    ErrD(u8),
80    /// SQLWARN0 to SQLWARNA as 0 to 10.
81    Warn(u8),
82}
83
84codec_struct!(SqlEntry { ordinal, verb, statement, text, fingerprint, with_hold });
85codec_enum!(SqlStatement {
86    Query { inputs, into } = 0,
87    Change { delete, inputs, current_of } = 1,
88    Open { cursor, inputs } = 2,
89    Fetch { cursor, into } = 3,
90    Close { cursor } = 4,
91    Commit = 5,
92    Rollback = 6,
93    Declaration = 7,
94    Unsupported(what) = 8,
95    Connect { what, location } = 9,
96    Prepare { name, source } = 10,
97    ExecuteImmediate { source } = 11,
98    Execute { name, inputs } = 12,
99    OpenPrepared { cursor, statement, inputs } = 13,
100});
101codec_struct!(HostPlace { var, member, ty, indicator } check host_place_valid);
102codec_struct!(Sqlca { fields } check sqlca_valid);
103codec_enum!(SqlcaField {
104    CaId = 0,
105    CaBc = 1,
106    Code = 2,
107    ErrMl = 3,
108    ErrMc = 4,
109    ErrP = 5,
110    State = 6,
111    ErrD(n) = 7,
112    Warn(n) = 8,
113});
114
115/// `crate::sql::read` and `write` take a structure's members one by one, never the structure.
116fn not_a_structure(ty: &HostType) -> Result<(), String> {
117    match ty {
118        HostType::Structure(_) => Err("a host structure where lowering gives its members".into()),
119        _ => Ok(()),
120    }
121}
122
123fn host_place_valid(place: &HostPlace) -> Result<(), String> {
124    place.ty.as_ref().map_or(Ok(()), not_a_structure)
125}
126
127fn sqlca_valid(sqlca: &Sqlca) -> Result<(), String> {
128    for (field, _, ty) in &sqlca.fields {
129        match *field {
130            SqlcaField::ErrD(n) if !(1..=6).contains(&n) => return Err(format!("SQLERRD({n}) is not an SQLCA field")),
131            SqlcaField::Warn(n) if n > 10 => return Err(format!("SQLWARN{n} is not an SQLCA field")),
132            _ => not_a_structure(ty)?,
133        }
134    }
135    Ok(())
136}
137
138/// load-module.md §7: ordinals run from 1, each fingerprint is its text's, and only the OPEN of a
139/// cursor declared WITH HOLD says so.
140pub(super) fn table_valid(table: &[SqlEntry], symbols: &[String]) -> Result<(), String> {
141    let symbol = |id: SymId| symbols.get(id as usize).ok_or_else(|| format!("symbol {id} of a table of {}", symbols.len()));
142    for (k, entry) in (1u32..).zip(table) {
143        if entry.ordinal != k {
144            return Err(format!("SQL entry {k} has ordinal {}", entry.ordinal));
145        }
146        let text = symbol(entry.text)?;
147        if entry.fingerprint != fingerprint(text) {
148            return Err(format!("SQL entry {k} has fingerprint {:08X}, not its text's {:08X}", entry.fingerprint, fingerprint(text)));
149        }
150        let held = match &entry.statement {
151            SqlStatement::Open { cursor, .. } | SqlStatement::OpenPrepared { cursor, .. } => text.starts_with(&format!("DECLARE {} CURSOR WITH HOLD FOR ", symbol(*cursor)?)),
152            _ => false,
153        };
154        if entry.with_hold != held {
155            return Err(format!("SQL entry {k} has WITH HOLD {} for its text", if entry.with_hold { "set" } else { "clear" }));
156        }
157    }
158    Ok(())
159}
ironwork_rt/lir/sql.rs

ironwork_rt/lir/
sql.rs
