memf_strings/
from_file.rs

1//! Parser for pre-extracted string files (one string per line).
2//!
3//! Supports two formats:
4//! 1. Raw: one string per line (no offset info)
5//! 2. Offset-prefixed: `<offset>: <string>` (decimal or hex offset)
6
7use crate::{ClassifiedString, Result, StringEncoding};
8use std::io::BufRead;
9use std::path::Path;
10
11/// Parse a pre-extracted strings file into `ClassifiedString` values.
12///
13/// Each line becomes one `ClassifiedString` with empty categories
14/// (to be classified later by the pipeline).
15pub fn from_strings_file(path: &Path) -> Result<Vec<ClassifiedString>> {
16    let file = std::fs::File::open(path)?;
17    let reader = std::io::BufReader::new(file);
18    let mut results = Vec::new();
19
20    for (line_num, line) in reader.lines().enumerate() {
21        let line = line?;
22        let trimmed = line.trim_end();
23        if trimmed.is_empty() {
24            continue;
25        }
26
27        let (offset, value) = parse_line(trimmed, line_num as u64);
28        results.push(ClassifiedString {
29            value,
30            physical_offset: offset,
31            encoding: StringEncoding::Ascii,
32            categories: Vec::new(),
33        });
34    }
35
36    Ok(results)
37}
38
39/// Parse a single line, detecting offset-prefixed format.
40fn parse_line(line: &str, line_num: u64) -> (u64, String) {
41    // Try offset-prefixed format: "1234: some string" or "0x1234: some string"
42    if let Some(colon_pos) = line.find(": ") {
43        let prefix = &line[..colon_pos];
44        let prefix = prefix.trim();
45        if let Some(offset) = parse_offset(prefix) {
46            let value = line[colon_pos + 2..].to_string();
47            return (offset, value);
48        }
49    }
50    // Raw format: use line number as pseudo-offset
51    (line_num, line.to_string())
52}
53
54fn parse_offset(s: &str) -> Option<u64> {
55    if let Some(hex) = s.strip_prefix("0x").or_else(|| s.strip_prefix("0X")) {
56        u64::from_str_radix(hex, 16).ok()
57    } else {
58        s.parse::<u64>().ok()
59    }
60}
61
62#[cfg(test)]
63mod tests {
64    use super::*;
65    use std::io::Write;
66
67    fn write_temp_file(content: &str) -> std::path::PathBuf {
68        use std::collections::hash_map::DefaultHasher;
69        use std::hash::{Hash, Hasher};
70        let mut h = DefaultHasher::new();
71        std::thread::current().name().hash(&mut h);
72        content.len().hash(&mut h);
73        let unique = h.finish();
74        let path = std::env::temp_dir().join(format!(
75            "memf_test_strings_{}_{}",
76            std::process::id(),
77            unique
78        ));
79        let mut f = std::fs::File::create(&path).unwrap();
80        f.write_all(content.as_bytes()).unwrap();
81        path
82    }
83
84    #[test]
85    fn raw_format() {
86        let path = write_temp_file("Hello World\n/etc/passwd\nhttps://evil.com\n");
87        let strings = from_strings_file(&path).unwrap();
88        assert_eq!(strings.len(), 3);
89        assert_eq!(strings[0].value, "Hello World");
90        assert_eq!(strings[1].value, "/etc/passwd");
91        assert_eq!(strings[2].value, "https://evil.com");
92        std::fs::remove_file(&path).ok();
93    }
94
95    #[test]
96    fn offset_prefixed_decimal() {
97        let path = write_temp_file("1000: Hello\n2000: World\n");
98        let strings = from_strings_file(&path).unwrap();
99        assert_eq!(strings.len(), 2);
100        assert_eq!(strings[0].physical_offset, 1000);
101        assert_eq!(strings[0].value, "Hello");
102        assert_eq!(strings[1].physical_offset, 2000);
103        std::fs::remove_file(&path).ok();
104    }
105
106    #[test]
107    fn offset_prefixed_hex() {
108        let path = write_temp_file("0x1A2B: hex string\n");
109        let strings = from_strings_file(&path).unwrap();
110        assert_eq!(strings.len(), 1);
111        assert_eq!(strings[0].physical_offset, 0x1A2B);
112        assert_eq!(strings[0].value, "hex string");
113        std::fs::remove_file(&path).ok();
114    }
115
116    #[test]
117    fn skips_empty_lines() {
118        let path = write_temp_file("line1\n\n\nline2\n");
119        let strings = from_strings_file(&path).unwrap();
120        assert_eq!(strings.len(), 2);
121        std::fs::remove_file(&path).ok();
122    }
123
124    #[test]
125    fn string_with_colon_but_no_offset() {
126        let path = write_temp_file("http://example.com:8080/path\n");
127        let strings = from_strings_file(&path).unwrap();
128        assert_eq!(strings.len(), 1);
129        // "http" is not a valid offset, so the whole line is the value
130        assert_eq!(strings[0].value, "http://example.com:8080/path");
131        std::fs::remove_file(&path).ok();
132    }
133
134    #[test]
135    fn malformed_offset_line() {
136        // "notanumber: some text" — the prefix "notanumber" is not a valid offset,
137        // so the whole line should be treated as raw format.
138        let path = write_temp_file("notanumber: some text\n");
139        let strings = from_strings_file(&path).unwrap();
140        assert_eq!(strings.len(), 1);
141        // Since "notanumber" can't be parsed as u64, the entire line is the value
142        assert_eq!(strings[0].value, "notanumber: some text");
143        assert_eq!(strings[0].physical_offset, 0); // line_num 0
144        std::fs::remove_file(&path).ok();
145    }
146
147    #[test]
148    fn offset_prefixed_hex_uppercase() {
149        let path = write_temp_file("0XFF00: uppercase hex\n");
150        let strings = from_strings_file(&path).unwrap();
151        assert_eq!(strings.len(), 1);
152        assert_eq!(strings[0].physical_offset, 0xFF00);
153        assert_eq!(strings[0].value, "uppercase hex");
154        std::fs::remove_file(&path).ok();
155    }
156
157    #[test]
158    fn parse_offset_helper() {
159        assert_eq!(parse_offset("0x1234"), Some(0x1234));
160        assert_eq!(parse_offset("0X1234"), Some(0x1234));
161        assert_eq!(parse_offset("42"), Some(42));
162        assert_eq!(parse_offset("abc"), None);
163        assert_eq!(parse_offset(""), None);
164    }
165}
memf_strings/from_file.rs

memf_strings/
from_file.rs
