Update main.cpp

[LezheGao]

Fixes #1544

Description of the Change

Reorder the initialization sequence in init_core_client() to ensure that command-line arguments correctly override settings from cc_config.xml.

Before: command-line parsing happened before reading the config file, so XML values unconditionally overwrote the earlier command-line settings.
After:

1. The --dir/-dir argument is extracted and handled early to change the working directory before any config file is read.
2. cc_config.defaults() and nvc_config.defaults() are called.
3. A first pass of gstate.parse_cmdline() parses all remaining arguments.
4. read_config_file(true) loads cc_config.xml from the now-correct working directory.
5. A second pass of gstate.parse_cmdline() re-applies all command-line options, which now take precedence over the XML-loaded values.

This change also updates do_gpu_detection() to follow the same pattern (read config first, then parse command line), keeping behaviour consistent.
Assisted-by: (not using an agent): DeepSeek-V4

Alternate Designs
Two other approaches were considered:

1. Add source-tracking flags – extend CC_CONFIG with per-option set_by_cmdline booleans and skip XML assignment when that flag is true. This is more invasive, touches many configuration members, and increases maintenance overhead.
2. Swap only the order without handling --dir specially – but this would break if cc_config.xml is not in the current directory when the client starts, because the directory change would happen after reading the file.

The chosen design is the simplest and least intrusive: it uses the existing parsing mechanism twice, requiring no changes to parse_options_client() or CC_CONFIG structure, and correctly handles directory changes.

Release Notes
Fix command-line options being overridden by cc_config.xml; command‑line arguments now take precedence over the configuration file.

---

Summary by cubic

Command-line arguments now correctly override cc_config.xml across platforms. init_core_client(): extract and apply --dir before first parse, switch to the data dir (or default on Windows), read config, then re-parse CLI to override; do_gpu_detection(): read config before CLI parse and remove the late read so diagnostics honor flags.

^{Written for commit 5d583a4. Summary will update on new commits.}

[cubic-dev-ai]

All reported issues were addressed across 1 file

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

All reported issues were addressed

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

All reported issues were addressed

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="client/main.cpp">

<violation number="1" location="client/main.cpp:194">
P2: Behavior regression in `--dir` error handling. The previous `-dir` branch in `parse_cmdline` did `if (chdir(argv[++i])) { perror("chdir"); exit(1); }`, so a bad directory terminated the client. The new code only logs an error and continues, and it sets `dir_specified = true` even when the chdir failed. As a result, on Windows the `chdir_to_data_dir()` fallback is also skipped (because `dir_specified` is true), and the client runs on with an unexpected working directory instead of failing fast as before.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

P2: Behavior regression in --dir error handling. The previous -dir branch in parse_cmdline did if (chdir(argv[++i])) { perror("chdir"); exit(1); }, so a bad directory terminated the client. The new code only logs an error and continues, and it sets dir_specified = true even when the chdir failed. As a result, on Windows the chdir_to_data_dir() fallback is also skipped (because dir_specified is true), and the client runs on with an unexpected working directory instead of failing fast as before.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At client/main.cpp, line 194:

<comment>Behavior regression in `--dir` error handling. The previous `-dir` branch in `parse_cmdline` did `if (chdir(argv[++i])) { perror("chdir"); exit(1); }`, so a bad directory terminated the client. The new code only logs an error and continues, and it sets `dir_specified = true` even when the chdir failed. As a result, on Windows the `chdir_to_data_dir()` fallback is also skipped (because `dir_specified` is true), and the client runs on with an unexpected working directory instead of failing fast as before.</comment>

<file context>
@@ -180,17 +180,46 @@ static void init_core_client(int argc, char** argv) {
+                    argv[j] = argv[j+2];
+                }
+                argc -= 2;
+                if (boinc_chdir(dir_path)) {
+                    log_message_error("Failed to chdir to specified directory");
+                }
</file context>

[davidpanderson]

The BOINC docs don't specify the priority of

• config file
• cmdline args
• env vars

So I suggest that we leave things the way they are.

[AenBleidd]

We need to specify this somewhere to avoid misunderstandings.
I'll note this, and we discuss during one of the next calls.

[AenBleidd]

@davidpanderson, I did a little research on this topic.
The general priorities list is the next (from lowest priority to highest priority):

1. Build-in defaults
2. Configuration file
3. Environment variables
4. Command-line parameters

I think we should document this and fix it whenever possible to follow this priorities list.
But before doing that, let's discuss it.