Regex Patterns

Predefined regex patterns for common validation scenarios.

Regex Dependency

Regex validation requires PCRE2. If compiled without regex support (-Dregex=false), these patterns return stub implementations that report "Regex support disabled".

Usage

#include "argus/regex.h"

OPTION_STRING('e', "email", HELP("Email address"),
              VALIDATOR(V_REGEX(ARGUS_RE_EMAIL)))

Network Patterns

IP Addresses

Pattern	Validates	Example
`ARGUS_RE_IPV4`	IPv4 addresses	`192.168.1.1`
`ARGUS_RE_IP4CIDR`	IPv4 with optional CIDR	`192.168.1.0/24`
`ARGUS_RE_IPV6`	IPv6 addresses	`2001:db8::1`

OPTION_STRING('i', "ip", HELP("Server IP address"),
              VALIDATOR(V_REGEX(ARGUS_RE_IPV4)))

OPTION_STRING('n', "network", HELP("Network range"),
              VALIDATOR(V_REGEX(ARGUS_RE_IP4CIDR)))

Network Infrastructure

Pattern	Validates	Example
`ARGUS_RE_MAC`	MAC addresses	`01:23:45:67:89:AB`
`ARGUS_RE_DOMAIN`	Domain names (FQDN)	`example.com`
`ARGUS_RE_PORT`	Port numbers (1-65535)	`8080`

OPTION_STRING('m', "mac", HELP("MAC address"),
              VALIDATOR(V_REGEX(ARGUS_RE_MAC)))

OPTION_STRING('d', "domain", HELP("Domain name"),
              VALIDATOR(V_REGEX(ARGUS_RE_DOMAIN)))

URLs

Pattern	Validates	Example
`ARGUS_RE_URL`	Any protocol URL	`https://example.com/path`
`ARGUS_RE_HTTP`	HTTP(S) URLs only	`http://example.com`
`ARGUS_RE_FILE_URL`	File URLs	`file:///path/to/file`

OPTION_STRING('u', "url", HELP("Website URL"),
              VALIDATOR(V_REGEX(ARGUS_RE_URL)))

OPTION_STRING('a', "api", HELP("API endpoint"),
              VALIDATOR(V_REGEX(ARGUS_RE_HTTP)))

Communication Patterns

Email

Pattern	Validates	Example
`ARGUS_RE_EMAIL`	Basic email format	`user@example.com`
`ARGUS_RE_EMAIL_STRICT`	RFC-compliant email	`user.name+tag@example.com`

OPTION_STRING('e', "email", HELP("Email address"),
              VALIDATOR(V_REGEX(ARGUS_RE_EMAIL)))

OPTION_STRING('c', "contact", HELP("Contact email (strict)"),
              VALIDATOR(V_REGEX(ARGUS_RE_EMAIL_STRICT)))

Phone Numbers

Pattern	Validates	Example
`ARGUS_RE_PHONE_INTL`	International format	`+12345678901`
`ARGUS_RE_PHONE_US`	US phone numbers	`123-456-7890`
`ARGUS_RE_PHONE_EU`	European phone numbers	`+33 123456789`

OPTION_STRING('p', "phone", HELP("Phone number"),
              VALIDATOR(V_REGEX(ARGUS_RE_PHONE_US)))

Date and Time Patterns

Pattern	Validates	Example
`ARGUS_RE_ISO_DATE`	ISO date (YYYY-MM-DD)	`2024-03-15`
`ARGUS_RE_ISOTIME`	ISO datetime	`2024-03-15T14:30:00`
`ARGUS_RE_US_DATE`	US date format	`03/15/2024`
`ARGUS_RE_EU_DATE`	European date format	`15/03/2024`
`ARGUS_RE_TIME24`	24-hour time	`14:30:00`

OPTION_STRING('d', "date", HELP("Date (YYYY-MM-DD)"),
              VALIDATOR(V_REGEX(ARGUS_RE_ISO_DATE)))

OPTION_STRING('t', "time", HELP("Time (HH:MM:SS)"),
              VALIDATOR(V_REGEX(ARGUS_RE_TIME24)))

Geographic Patterns

Pattern	Validates	Example
`ARGUS_RE_ZIP`	US ZIP codes	`12345` or `12345-6789`
`ARGUS_RE_UK_POST`	UK postcodes	`SW1A 1AA`
`ARGUS_RE_CA_POST`	Canadian postal codes	`A1A 1A1`
`ARGUS_RE_LATITUDE`	Latitude (-90 to 90)	`40.7128`
`ARGUS_RE_LONGITUDE`	Longitude (-180 to 180)	`-74.0060`

OPTION_STRING('z', "zip", HELP("ZIP code"),
              VALIDATOR(V_REGEX(ARGUS_RE_ZIP)))

OPTION_STRING('l', "lat", HELP("Latitude"),
              VALIDATOR(V_REGEX(ARGUS_RE_LATITUDE)))

Security Patterns

Pattern	Validates	Example
`ARGUS_RE_USER`	Username (3-20 chars)	`user_123`
`ARGUS_RE_PASSWD`	Basic password	`password123`
`ARGUS_RE_PASSWD_STRONG`	Strong password	`Pass123!`
`ARGUS_RE_UUID`	UUID v4 format	`550e8400-e29b-41d4-a716-446655440000`

OPTION_STRING('u', "username", HELP("Username"),
              VALIDATOR(V_REGEX(ARGUS_RE_USER)))

OPTION_STRING('p', "password", HELP("Strong password"),
              VALIDATOR(V_REGEX(ARGUS_RE_PASSWD_STRONG)))

File System Patterns

Pattern	Validates	Example
`ARGUS_RE_UNIX_PATH`	Unix absolute paths	`/path/to/file`
`ARGUS_RE_WIN_PATH`	Windows absolute paths	`C:\folder\file`
`ARGUS_RE_FILENAME`	Filename with extension	`document.pdf`

OPTION_STRING('f', "file", HELP("File path"),
              VALIDATOR(V_REGEX(ARGUS_RE_UNIX_PATH)))

OPTION_STRING('n', "name", HELP("Filename"),
              VALIDATOR(V_REGEX(ARGUS_RE_FILENAME)))

Visual and Data Patterns

Colors

Pattern	Validates	Example
`ARGUS_RE_HEX_COLOR`	Hex colors	`#FF0000` or `#F00`
`ARGUS_RE_RGB`	RGB color format	`rgb(255,0,0)`

OPTION_STRING('c', "color", HELP("Hex color"),
              VALIDATOR(V_REGEX(ARGUS_RE_HEX_COLOR)))

Numbers and Formats

Pattern	Validates	Example
`ARGUS_RE_SEMVER`	Semantic version	`1.2.3` or `1.0.0-beta+build`
`ARGUS_RE_POS_INT`	Positive integers	`123`
`ARGUS_RE_NEG_INT`	Negative integers	`-123`
`ARGUS_RE_FLOAT`	Decimal numbers	`3.14` or `-2.7`
`ARGUS_RE_HEX`	Hex numbers	`0x1A3F`

OPTION_STRING('v', "version", HELP("Semantic version"),
              VALIDATOR(V_REGEX(ARGUS_RE_SEMVER)))

OPTION_STRING('h', "hex", HELP("Hex number"),
              VALIDATOR(V_REGEX(ARGUS_RE_HEX)))

Custom Patterns

Define your own patterns using MAKE_REGEX:

// Define at file scope
#define RE_PRODUCT_ID MAKE_REGEX("^[A-Z]{2}\\d{4}-[A-Z0-9]{6}$", "Format: XX0000-XXXXXX")
#define RE_LICENSE_KEY MAKE_REGEX("^[A-Z0-9]{4}-[A-Z0-9]{4}-[A-Z0-9]{4}$", "Format: XXXX-XXXX-XXXX")

ARGUS_OPTIONS(options,
    OPTION_STRING('p', "product", HELP("Product ID"),
                  VALIDATOR(V_REGEX(RE_PRODUCT_ID))),
    
    OPTION_STRING('k', "key", HELP("License key"),
                  VALIDATOR(V_REGEX(RE_LICENSE_KEY)))
)

Pattern Testing

Test patterns before use:

# Valid examples
./app --email user@example.com          # ✅ Matches ARGUS_RE_EMAIL
./app --ip 192.168.1.1                  # ✅ Matches ARGUS_RE_IPV4  
./app --date 2024-03-15                  # ✅ Matches ARGUS_RE_ISO_DATE

# Invalid examples  
./app --email invalid-email             # ❌ Error: Invalid value 'invalid-email': Enter email: user@example.com
./app --ip 999.999.999.999              # ❌ Error: Invalid value '999.999.999.999': Enter valid IPv4: 192.168.1.1
./app --date 03-15-2024                  # ❌ Error: Invalid value '03-15-2024': Enter date: YYYY-MM-DD

Error Messages

Each pattern includes helpful error hints:

ARGUS_RE_EMAIL: "Enter email: user@example.com"
ARGUS_RE_IPV4: "Enter valid IPv4: 192.168.1.1"
ARGUS_RE_PHONE_US: "Enter US phone: 123-456-7890"
ARGUS_RE_ISO_DATE: "Enter date: YYYY-MM-DD"

Custom patterns should include similar hints:

#define RE_CUSTOM MAKE_REGEX("pattern", "Clear format description")

Performance Notes

Patterns are compiled once at first use
Complex patterns (like IPv6) may impact startup time
Use simpler validation when regex isn't needed

What's Next?

Custom Validators - Create domain-specific validation
Validation - Combine regex with other validators
Examples - See patterns in real applications

Usage​

Network Patterns​

IP Addresses​

Network Infrastructure​

URLs​

Communication Patterns​

Email​

Phone Numbers​

Date and Time Patterns​

Geographic Patterns​

Security Patterns​

File System Patterns​

Visual and Data Patterns​

Colors​

Numbers and Formats​

Custom Patterns​

Pattern Testing​

Error Messages​

Performance Notes​

What's Next?​