Crate fstapi

Rust wrapper of APIs for manipulating Fast Signal Trace (FST) format waveforms.

FST is an open source file format for storing digital waveforms from HDL simulations. It was created by the author of GTKWave in 2014, as an alternate to the VCD (Value Change Dump) format.

For more details, please see:

• The source code of GTKWave.
• The documentation of GTKWave.
• An unofficial specification for FST format.

Examples

Create an FST waveform:

use fstapi::{Writer, var_type, var_dir};

// Create the waveform.
let mut writer = Writer::create("hello.fst", true)?
  .comment("FST waveform example")?
  .timescale_from_str("1ns")?;

// Create a variable.
let var = writer.create_var(var_type::VCD_REG, var_dir::OUTPUT, 8, "var", None)?;

// Emit value change data and time change data.
writer.emit_value_change(var, b"10001000")?;
writer.emit_time_change(10)?;
writer.emit_value_change(var, b"10011100")?;
writer.emit_time_change(42)?;
writer.emit_value_change(var, b"00111001")?;
writer.emit_time_change(100)?;

Print all variables of an FST waveform:

let mut reader = fstapi::Reader::open("hello.fst")?;
for var in reader.vars() {
  let (name, _) = var?;
  println!("{name}");
}

More Examples

See the GitHub repository: fst-tools, which contains 3 command line tools with this library for manipulating FST waveforms.

Modules

array_type

Enum values of type ArrayType.

attr_type

Enum values of type AttrType.

block_type

Enum values of type BlockType.

enum_value_type

Enum values of type EnumValueType.

file_type

Enum values of type FileType.

misc_type

Enum values of type MiscType.

pack_type

Enum values of type PackType.

scope_type

Enum values of type ScopeType.

supplemental_data_type

Enum values of type SupplementalDataType.

supplemental_var_type

Enum values of type SupplementalVarType.

var_dir

Enum values of type VarDir.

var_type

Enum values of type VarType.

writer_pack_type

Enum values of type WriterPackType.

Structs

Attr

An attribute in FST hierarchy.

Handle

Handle type, which is actually a 32-bit non-zero unsigned integer.

Hiers

An iterator over the hierarchies of an FST waveform.

Reader

FST waveform reader.

Scope

A scope in FST hierarchy.

Var

A variable in FST hierarchy.

Vars

An iterator over the variables of an FST waveform.

Writer

FST waveform writer.

Enums

Error

Error that may returned from FST-related APIs.

Hier

Hierarchy of FST waveform.

Type Definitions

ArrayType

Subtype of the attribute of type ARRAY. Subtype of the attribute of type ARRAY.

AttrType

Type of attribute. Type of attribute.

BlockType

Type of block. Type of block.

EnumValueType

Subtype of the attribute of type ENUM. Subtype of the attribute of type ENUM.

FileType

Type of file. Type of file.

MiscType

Subtype of the attribute of type MISC. Subtype of the attribute of type MISC.

PackType

Subtype of the attribute of type PACK. Subtype of the attribute of type PACK.

Result

Result with error type Error.

ScopeType

Type of scope. Type of scope.

SupplementalDataType

Type of supplemental data. Type of supplemental data.

SupplementalVarType

Type of supplemental variable. Type of supplemental variable.

VarDir

Type of variable direction. Type of variable direction.

VarType

Type of variable. Type of variable.

WriterPackType

Type of packaging method of writer. Type of packaging method of writer.