RDKB-65989: Move MAP-T ratio calculation to WanManager from DHCPManager

[sivaraj-comcast]

RDKB-65989: Move MAP-T ratio calculation to WanManager from DHCPManager

Reason for change: Remove duplicated ratio computation from DHCPManager. DHCPManager now sends ratio=0 in the rbus event; WanManager derives ratio from psidLen as the single authoritative owner.

Test Procedure: Verify "sysevent get mapt_ratio" and Device.MAP.Domain.1.Rule.1.X_RDKCENTRAL-COM_Ratio / Device.DHCPv6.Client.1.X_RDKCENTRAL-COM_RcvOption.MapRatio is correctly set by WanManager after MAPT is configured.
Risks: Low
Priority: P1
Signed-off-by: Sivaraj_Sivalingam@comcast.com

[Copilot]

Pull request overview

This PR aligns MAP-T ratio ownership with the stated design: DHCPManager stops computing MAP-T ratio during DHCP option parsing, and instead leaves the ratio value unset (effectively 0) so WanManager can derive it from PSID length as the single authoritative source.

Changes:

• Removed MAP-T ratio calculation from DHCPManager’s MAP option parsing logic.
• Removed associated MAP-T ratio trace logging from the DHCP parsing path.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

Suppressed comments (1)

source/DHCPMgrUtils/dhcpmgr_map_apis.c:209

• WanManager is expected to derive MAP-T ratio from psidLen, but when the S46 Port Params suboption is absent (bytesLeftOut == 0) this parser never sets a default g_stMapData.PsidLen (it stays 0 from the earlier memset). With this PR also forcing Ratio = 0, downstream components will have neither a ratio nor a reliable psidLen to derive it from. Consider deriving/validating a default PsidLen from EaLen and RuleIPv4PrefixLen per RFC (and still keep Ratio = 0 so DHCPManager is not computing it).

               g_stMapData.Ratio = 0;
               g_stMapData.PsidOffset = 6;
               MAP_LOG_INFO("<<<TRACE>>> bytesLeftOut                   : %u", bytesLeftOut);

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Suppressed comments (1)

source/DHCPMgrUtils/dhcpmgr_map_apis.c:462

• DhcpMgr_MapParseOptResponse no longer sets map->ratio, but the RBUS path still reads mapt->ratio to populate MapRatio (e.g., dhcpmgr_rbus_apis.c:216). That makes the published ratio depend on the caller having zero-initialized the ipc_map_data_t. To keep this API deterministic and aligned with the new design (DHCPManager publishes ratio=0 and WanManager derives the real ratio), explicitly set map->ratio = 0 here.

     map->v4Len = g_stMapData.RuleIPv4PrefixLen;
     map->psidOffset = g_stMapData.PsidOffset;
     map->psidLen = g_stMapData.PsidLen;
     map->psid = g_stMapData.Psid;
     map->iapdPrefixLen = g_stMapData.PdIPv6PrefixLen;