ESP32 - Update advertising data to be closer to the spec

[vivien-apple]

Problem

This PR update the ble advertising data to get it closer to the spec.

Summary of Changes

• Update the advertising data on the esp32
• Change the connection delegate to use the content of the advertising data instead of the connection name to connect to the peripheral
• Change the code in examples/chip-tool/ to pass the discriminator instead of a name
• Change the code in src/darwin to pass the discriminator instead of a name

[github-actions]

Size increase report for "gn_nrf-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

[github-actions]

Size increase report for "gn_linux-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

[github-actions]

Size increase report for "nrf-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-nrf52840-lock-example.out and ./pull_artifact/chip-nrf52840-lock-example.out:

sections,vmsize,filesize
.debug_str,0,7
.debug_info,0,-7
[Unmapped],0,-7
.debug_loc,0,-13

[github-actions]

Size increase report for "linux-example-build"

File	Section	File	VM
chip-standalone-demo.out	.text	208	208
chip-standalone-demo.out	.dynsym	72	72
chip-standalone-demo.out	.rela.plt	72	72
chip-standalone-demo.out	.dynstr	71	71
chip-standalone-demo.out	.plt	48	48
chip-standalone-demo.out	.plt.sec	48	48
chip-standalone-demo.out	.eh_frame	40	40
chip-standalone-demo.out	.got	24	24
chip-standalone-demo.out	.gnu.version	6	6
chip-standalone-demo.out	[LOAD #2 [R]]	-5	-5
chip-standalone-demo.out	[LOAD #5 [RW]]	-24	-24

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-standalone-demo.out and ./pull_artifact/chip-standalone-demo.out:

sections,vmsize,filesize
.debug_info,0,1591
.debug_str,0,1097
.debug_loc,0,1095
.debug_line,0,210
.text,208,208
.debug_ranges,0,160
.debug_abbrev,0,159
.dynsym,72,72
.rela.plt,72,72
.symtab,0,72
.dynstr,71,71
.strtab,0,57
.plt,48,48
.plt.sec,48,48
.eh_frame,40,40
.got,24,24
.gnu.version,6,6
[LOAD #2 [R]],-5,-5
[LOAD #5 [RW]],-24,-24
[Unmapped],0,-561

[github-actions]

Size increase report for "esp32-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-wifi-echo.elf and ./pull_artifact/chip-wifi-echo.elf:

BLOAT EXECUTION FAILED WITH CODE 1:
bloaty: integer overflow

[woody-apple]

@saurabhst @jelderton @BroderickCarlin ?

[andy31415]

supernit: how do people feel about early return and continues to decrease code indents? I find it easier to understand code if it is less indented once it starts growing, however I also see a pattern in other chip places of 'only one exit point' (but does that apply to non-resource constrained code?)

like:

if (![isConnectable boolValue]) {
  return;  // only connectable devices are useful
}

CBUUID * .....
for (....) {
  if (!... isEqualToData...) { 
     continue;
  }

  if (....) { 
  }
}

vs.

if ([isConnectable boolValue]) {
  CBUUID * .....;

  for (....) {
     if (...) { 
       if (...) {
       }
    }
  }
}

[vivien-apple]

For my part I'm 100% in favour or early returns and to declared variables just before they are used, if possible.
I think @gerickson advocates for the 'single exit point' patterns thought.

[andy31415]

does the size always need to be sizeof == MAX_ADV_DATA_LEN or could we use index here to reduce payload sizes? does it matter?

[vivien-apple]

At some point we will need to use manufacturer specific data and add them to the advertising data if there is enough space. The rest will go into the Scan Req/Resp packet.
I will dig into this when I will work on that in order to give you a more accurate answer.

[andy31415]

Will merge since my comments were more nit/meh. Would love an answer, however if we need to adjust code we can do it so in a separate PR.