Editing Param.sfo

==Description==
'''SFO''' ('''S'''ystem '''F'''ile '''O'''bject) are used in folders which content needs to be displayed in the [[XMB]].

*The values contained in a SFO can be simplyfied as inputs/outputs for/from the content:
**Boot modifyers (most of the int32 datas) that are sent to the content when is executed to activate specific features or settings (e.g. audio and video modes of a game).
**Information texts (most of the utf8 datas) about the content and its restrictions (e.g. title and version of a game).

'''SFX''' ('''S'''ystem '''F'''ile in '''X'''ML format) is similar than SFO but without the data related to its structure (the SFO metadata that has no real value).

The conversion between the 2 formats is direct because the important values contained in both formats are the same ('''version''', '''param_key''', '''param_fmt''', '''param_max_len''' & '''param_data''').

SFO's and SFX's can be chained in a structure of subfolders where the "main" SFO activates a special subfolder, and the subfolder contains another SFO that activates another subfolder and so on.

==Internal Structure==
===header===
At offset 0x0, length 0x14 (20 bytes)
{{Boxcode|content=<syntaxhighlight lang="c">
struct sfo_header
{
uint32_t magic; /************ Always PSF */
uint32_t version; /********** Usually 1.1 */
uint32_t key_table_start; /** Start offset of key_table */
uint32_t data_table_start; /* Start offset of data_table */
uint32_t tables_entries; /*** Number of entries in all tables */
};
</syntaxhighlight>}}

===index_table===
At offset 0x14, composed by a number of entries defined with '''tables_entries''' in the '''header''', each entry is 0x10 length (16 bytes). Values are in Little Endian.

Every entry belongs to a '''key''' name in the '''key_table''' and defines a '''data''' area in the '''data_table'''

{{Boxcode|content=<syntaxhighlight lang="c">
struct sfo_index_table_entry
{
uint16_t key_offset; /*** param_key offset (relative to start offset of key_table) */
uint16_t data_fmt; /***** param_data data type */
uint32_t data_len; /***** param_data used bytes */
uint32_t data_max_len; /* param_data total bytes */
uint32_t data_offset; /** param_data offset (relative to start offset of data_table) */
};
</syntaxhighlight>}}

{| class="wikitable" style="margin:auto"
|+Data Types
! colspan=2 | fmt !! rowspan=2 | Data Type !! rowspan=2 | Description !! rowspan=2 | Notes
|-
! In SFO !! In SFX
|-
| 04 00 || {{no}}? || {{cellcolors|brown|yellow}} utf8-S || utf8 Special Mode, '''NOT''' NULL terminated || Used in SFO's generated by the system and/or linked to an user ([[Game Saves]] and [[Trophy files|Trophies]]). See {{talk}} page
|-
| 04 02 || utf8 || {{cellcolors|brown|white}} utf8 || utf8 character string, NULL terminated (0x00) || Can be used any character from the system [[XMB Fonts|fonts]]. The NULL byte is counted as part of the used bytes in '''len'''
|-
| 04 04 || int32 || {{cellcolors|black|lime}} int32 || integer 32 bits unsigned || Allways has a length of 4 bytes in '''len''' and '''max_len''' (even in the case some bytes are not used, all them are marked as used)
|-
|}

===key_table===
Composed by a number of '''key''' entries defined with '''tables_entries''' in the '''header''', are short utf8 strings in capitals, NULL terminated (0x00), and ordered alphabetically (from A to Z). This alphabetically order defines the order of the associated entries in the other two tables ('''index_table''', and '''data_table''')

The end offset of this table needs to be aligned to a multiply of 32bits (4 bytes), this is made with a padding at the end of  '''key_table''' when needed (in a few SFO's the table is aligned naturally as a coincidence caused by the length of the '''key''' names used, when this happens there is no padding needed)

===data_table===
Composed by a number of '''data''' entries defined with '''tables_entries''' in the '''header''', every entry in this table is defined by the associated entry in the '''index_table''' by using: '''fmt''', '''len''', '''max_len''', and '''offset'''. There is no padding between entries neither at the end of this table

Some '''data''' entries can be filled with zeroes (not used, but availables for being used). This entries can be considered reserved, and are marked with a '''len''' = 0 in the associated entry in the '''index_table'''


==Internal Structure Examples==
Both example files (SFO & SFX) are hand made (the structure is correct but are only a minimal example). Both contains the same info but in different format: only 1 entry (TITLE_ID) and the value for this entry (BLUS12345)

*The bigger difference between SFO and SFX is SFX doesnt contains:
**SFO header
**Key and Data offsets
**Data used length

''This Structure was taken from PS3 SFO''
''There is no TITLE_ID inside PSP SFO''

===SFO===
 Offset(h) 00 01 02 03  04 05 06 07  08 09 0A 0B  0C 0D 0E 0F
      0x00 <span style="background:#ff6666;">00 50 53 46</span>  <span style="background:#ff6666;">01 01 00 00</span>  <span style="background:#ff6666;">24 00 00 00</span>  <span style="background:#ff6666;">30 00 00 00</span> | <span style="background:#ff6666;">.PSF....$...0...</span> |
      0x10 <span style="background:#ff6666;">01 00 00 00</span>  <span style="background:#66ff66;">00 00</span> <span style="background:#66ff66;">04 02</span>  <span style="background:#66ff66;">0A 00 00 00</span>  <span style="background:#66ff66;">0F 00 00 00</span> | <span style="background:#ff6666;">....</span><span style="background:#66ff66;">............</span> |
      0x20 <span style="background:#66ff66;">00 00 00 00</span>  <span style="background:#bbbbff;">54 49 54 4C  45 5F 49 44  00</span> <span style="background:lightgrey;">00 00 00</span> | <span style="background:#66ff66;">....</span><span style="background:#bbbbff;">TITLE_ID.</span><span style="background:lightgrey;">...</span> |
      0x30 <span style="background:#ffff66;">42 4C 55 53  31 32 33 34  35 00 00 00  00 00 00 00</span> | <span style="background:#ffff66;">BLUS12345.......</span> |

{| class="wikitable"
|-
! Areas !! Offset !! Size !! Name !! Example !! Notes
|-
! rowspan="5" | header
| 0x00 || 0x04 || '''magic''' || PSF ||
|-
| 0x04 || 0x04 || '''version''' || 01 01 00 00 || 1.01
|-
| 0x08 || 0x04 || '''key_table_start''' || 24 00 00 00 || Absolute start offset of <span style="background:#bbbbff;">'''key_table'''</span> = 0x24
|-
| 0x0C || 0x04 || '''data_table_start''' || 30 00 00 00 || Absolute start offset of <span style="background:#ffff66;">'''data_table'''</span> = 0x30
|-
| 0x10 || 0x04 || '''tables_entries''' || 01 00 00 00 || Number of entries in <span style="background:#66ff66;">'''index_table'''</span>, <span style="background:#bbbbff;">'''key_table'''</span>, and <span style="background:#ffff66;">'''data_table'''</span> = 1
|-
! rowspan="5" | index_table
| 0x14 || 0x02 || '''key_1_offset''' || 00 00 || '''key_1''' relative offset. (Absolute start offset of '''key_1''') - (Absolute start offset of <span style="background:#bbbbff;">'''key_table'''</span>) = 0x24-0x24 = 0
|-
| 0x16 || 0x02 || '''data_1_fmt''' || 04 02 || '''data_1''' data type = utf8
|-
| 0x18 || 0x04 || '''data_1_len''' || 0A 00 00 00 || '''data_1''' used length (BLUS12345 = 9 bytes + 1 byte NULL termination) = 10 bytes
|-
| 0x1C || 0x04 || '''data_1_max_len''' || 0F 00 00 00 || '''data_1''' total length. [[#TITLE_ID|TITLE_ID]] is always = 16 bytes
|-
| 0x20 || 0x04 || '''data_1_offset''' || 00 00 00 00 || '''data_1''' relative offset. (Absolute start offset of '''data_1''') - (Absolute start offset of <span style="background:#ffff66;">'''data_table'''</span>) = 0x30-0x30 = 0
|-
! key_table
|  0x24 || 0x09 || '''key_1''' || TITLE_ID || Relative offset defined in the <span style="background:#66ff66;">'''index_table'''</span>
|-{{cellcolors|lightgrey}}
| padding || 0x2D || 0x03 || ''padding'' || 00 00 00 || 9 bytes used by the previous entries + 3 padding = 12 (aligned to 4 bytes)
|-
! data_table
| 0x30 || 0x0F || '''data_1''' || BLUS12345 || Data type, used length, total length, and relative offset defined in the <span style="background:#66ff66;">'''index_table'''</span>
|}

===SFX===
{{Boxtip3|content= SFX are used in some disc with special content<br />SFX Can be used as "templates" to generate SFO files<br />SFX Can be created using a SFO as the "source". See: [[Dev_Tools#SFO2SFX|SFO2SFX]]}}

{{Boxcode|content=<syntaxhighlight lang="xml">
<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<paramsfo add_hidden="false">
  <param key="TITLE_ID" fmt="utf8" max_len="16">BLUS12345</param>
</paramsfo>
</syntaxhighlight>}}

*Notes
**The function of '''add_hidden="false"''' is unknown