A module had one channel back to its caller: the int returned from
dpm_module_execute, handed through by dpm_execute. Any detail behind
that number could only reach a log, so a caller wanting the reason had
to read output rather than ask for it.
dpm_set_last_error joins the exported API. A module records its reason
on the context handed to its entry point, which belongs to the caller,
and the caller reads it back with dpm_get_last_error.
The two accessors on the context now say what they do to it:
dpm_module_path becomes dpm_get_resolved_module_path, naming the value
it reports rather than the setting it came from, and dpm_last_error
becomes dpm_get_last_error, pairing with the setter.
Path normalization moves to sanitizers.cpp, which holds the conversions
that put a value written by a person into the single form the library
stores it in.
Namespace and extern "C" bodies are indented a level, so nesting is
visible from the indentation rather than only from the braces. Opening
braces stay on the line that opens the scope, including function
definitions, which previously carried theirs on a line of their own.
A module is built against the system-installed libdpm-core.so and is
responsible for being correct against it. Where it needs to act on the
version it is running under, dpm_core_version() reports that and the
module decides for itself.
dpm_module_core_min() is removed. It was a declaration handed to the
library to enforce on the module's behalf, and enforcement of that kind
belongs nowhere in a library that routes and hosts. The contract is now
three reserved symbols and load validation is two steps: the reserved
symbols resolve, and the version and description probes return
well-formed values.
compare_versions had no remaining caller and is removed; parse_version
stays for the well-formedness probe. The core_too_new fixture went with
the handshake it existed to exercise.
A module is addressed by name and command string, and nothing else.
Typed API access handed a caller a pointer into the callee's function
table, which meant compiling against that module's struct layout — a
build-time dependency between modules that the design does not permit.
Removing it also removes the manifest, the table magic constant, and
the table size field, which existed only to describe and validate
those tables.
Load validation is now three steps: reserved contract symbols resolve,
the minimum-version handshake passes, and the version and description
probes return well-formed values. The contract is four reserved
symbols, and a module's interface is the command vocabulary it
documents.
Documentation is brought in line, and artifacts are named exactly:
libdpm-core.so for the library, <dpm/core.h> for the header, the dpm
binary for the command-line tool.
dpm_require no longer takes a minimum version and applies no version
criterion of its own. A handle now means the module is valid, not that
it suits the caller. dpm_module_info_of is added alongside it, reporting
the name, version, description, and minimum-libdpm-core version read at
load, so a consuming module can judge a dependency's version for itself.
The one rule still enforced is the minimum-version handshake, where
libdpm-core is the host and refuses a module that demands a newer library
than the one running.
dpm_module_info_of joins the version script, so the exported surface is
now fourteen symbols under DPM_CORE_1.0.
Separately, the bare word "core" is gone from prose everywhere. It named
both the command-line tool and the library, so every use forced the
reader to guess which. Text now says "the dpm binary" or "libdpm-core".
Identifiers keep their spelling: libdpm-core, core.h, core.conf, the
"core" configuration namespace, dpm_core_version, core_min, DPM_CORE_1.0,
the dpmcore namespace, test_core, core_api.
Three user-visible strings changed with it: the load-refusal message now
reads "requires libdpm-core >= X, running libdpm-core is Y — update
libdpm-core", and the info module's description and help text name the
library. The test asserting on the refusal text was updated to match.
DESIGN.md's terminology line no longer defines "DPM Core" as the CLI,
which was the source of the ambiguity. OVERVIEW.md is restructured around
the three layers a reader meets DPM at — user, developer, filesystem —
so a code-level symbol never appears without saying whose layer it is.
MODULES.md describes the bundled info module as testing and demonstrating
full DPM system functionality rather than as a reference implementation.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
