SAFE_STRTO_ID_LIST(3)

💖 SAFE_STRTO_ID_LIST(3) — bestie, let’s parse some ids 💖

🌸 NAME 🌸

safe_strto_id_list, safe_strto_uid_list, safe_strto_gid_list — parse a string for ids and store them in the safe_id_range_list.

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✨ SYNOPSIS ✨

#include "safe_id_range_list.h"

struct safe_id_range_list;
typedef struct safe_id_range_list safe_id_range_list;

void safe_strto_id_list(safe_id_range_list list, const char *value,
       const char **endptr);
void safe_strto_uid_list(safe_id_range_list list, const char *value,
       const char **endptr);
void safe_strto_gid_list(safe_id_range_list list, const char *value,
       const char **endptr);

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🦋 DESCRIPTION 🦋

Okay so these functions add values to the list by parsing the value string. safe_strto_id_list only allows numeric values, while safe_strto_uid_list and safe_strto_gid_list allow non-numeric values that are converted to user and group ids respectively.

The functions safe_parse_id_list(3), safe_parse_uid_list(3), and safe_parse_gid_list(3) are simpler to use alternatives — lowkey convenient, fr fr.

🎀 Parameters 🎀

• list — The safe_id_range_list to add values to. Must be non-NULL.
• value — The range list string to parse. Must be non-NULL.
• endptr — If non-NULL, the value pointed to by this parameter will be updated to point to the location just past the last character of value parsed.

🌀 Range List Syntax 🌀

The syntax of a range list string is a set of ranges each separated by colons. Each range is either a single id, or a hyphen (-) separated set of ids — the first must be less than or equal to the second, and the second value may be a valid user or group name depending on the function used. If a user or group name is used as the first part of a range, the name must be separated from the hyphen by whitespace, because a hyphen is a legitimate character in a name.

⚠️ Parsing stops when an expected punctuation mark (- or :) is not found. This is not an error, and *endptr must be checked to detect this condition. Do not skip the vibe check on endptr, bestie 😭

A grammar for the range list is as follows:

<RANGE_LIST>
       := <RANGE>
       := <RANGE> <whitespace>* ':' <RANGE_LIST>

<RANGE>
       := <ID>
       := <ID> '-' <ID>
       := <ID> '-' <whitespace>* '*'

<ID>   := <whitespace>* <number>
       := <whitespace>* <text_name>

🌈 Example Range Lists 🌈

• 3 — Adds the value 3 to the list.
• 0:5:100-103 — Adds the values 0, 5, 100, 101, 102, and 103 to the list.
• root: user1 - user2 : 1000-* — When parsed with safe_strto_uid_list, adds the values 0, 500, 501 and 1000 and greater to the list assuming the user names root, user1 and user2 have the values 0, 500 and 501 respectively. The space after user1 is mandatory.

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💅 RETURN VALUE 💅

No return value, but errno is set to 0 on success and an appropriate value on error. Also endptr, if non-NULL, will be set to the location in value just past the last value parsed. Slay.

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💀 ERRORS 💀

• EINVAL — list or value was NULL. An invalid number or non-exist user or group name was encountered. The first element of a range was larger than the second. Or a value consisting entirely of whitespace was encountered.
• ERANGE — A numeric value was encountered that was too large.
• ENOMEM — A memory allocation failed.

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👑 AUTHOR 👑

James A. Kupsch — iconic, honestly.

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🫶 SEE ALSO 🫶

• safe_init_id_range_list(3)
• safe_destroy_id_range_list(3)
• safe_parse_id_list(3)
• safe_parse_uid_list(3)
• safe_parse_gid_list(3)

http://research.cs.wisc.edu/mist/safefile

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This page is dated 2011-07-26 and comes from the SAFE_STRTO_ID_LIST(3) manual. Stay safe out there, bestie 💖✨🎀