diff options
Diffstat (limited to 'vendor/backtrace/src/symbolize/gimli/parse_running_mmaps_unix.rs')
| -rw-r--r-- | vendor/backtrace/src/symbolize/gimli/parse_running_mmaps_unix.rs | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/vendor/backtrace/src/symbolize/gimli/parse_running_mmaps_unix.rs b/vendor/backtrace/src/symbolize/gimli/parse_running_mmaps_unix.rs new file mode 100644 index 000000000..a196ffcfb --- /dev/null +++ b/vendor/backtrace/src/symbolize/gimli/parse_running_mmaps_unix.rs @@ -0,0 +1,242 @@ +// Note: This file is only currently used on targets that call out to the code +// in `mod libs_dl_iterate_phdr` (e.g. linux, freebsd, ...); it may be more +// general purpose, but it hasn't been tested elsewhere. + +use super::mystd::fs::File; +use super::mystd::io::Read; +use super::mystd::str::FromStr; +use super::{OsString, String, Vec}; + +#[derive(PartialEq, Eq, Debug)] +pub(super) struct MapsEntry { + /// start (inclusive) and limit (exclusive) of address range. + address: (usize, usize), + /// The perms field are the permissions for the entry + /// + /// r = read + /// w = write + /// x = execute + /// s = shared + /// p = private (copy on write) + perms: [char; 4], + /// Offset into the file (or "whatever"). + offset: usize, + /// device (major, minor) + dev: (usize, usize), + /// inode on the device. 0 indicates that no inode is associated with the memory region (e.g. uninitalized data aka BSS). + inode: usize, + /// Usually the file backing the mapping. + /// + /// Note: The man page for proc includes a note about "coordination" by + /// using readelf to see the Offset field in ELF program headers. pnkfelix + /// is not yet sure if that is intended to be a comment on pathname, or what + /// form/purpose such coordination is meant to have. + /// + /// There are also some pseudo-paths: + /// "[stack]": The initial process's (aka main thread's) stack. + /// "[stack:<tid>]": a specific thread's stack. (This was only present for a limited range of Linux verisons; it was determined to be too expensive to provide.) + /// "[vdso]": Virtual dynamically linked shared object + /// "[heap]": The process's heap + /// + /// The pathname can be blank, which means it is an anonymous mapping + /// obtained via mmap. + /// + /// Newlines in pathname are replaced with an octal escape sequence. + /// + /// The pathname may have "(deleted)" appended onto it if the file-backed + /// path has been deleted. + /// + /// Note that modifications like the latter two indicated above imply that + /// in general the pathname may be ambiguous. (I.e. you cannot tell if the + /// denoted filename actually ended with the text "(deleted)", or if that + /// was added by the maps rendering. + pathname: OsString, +} + +pub(super) fn parse_maps() -> Result<Vec<MapsEntry>, &'static str> { + let mut v = Vec::new(); + let mut proc_self_maps = + File::open("/proc/self/maps").map_err(|_| "Couldn't open /proc/self/maps")?; + let mut buf = String::new(); + let _bytes_read = proc_self_maps + .read_to_string(&mut buf) + .map_err(|_| "Couldn't read /proc/self/maps")?; + for line in buf.lines() { + v.push(line.parse()?); + } + + Ok(v) +} + +impl MapsEntry { + pub(super) fn pathname(&self) -> &OsString { + &self.pathname + } + + pub(super) fn ip_matches(&self, ip: usize) -> bool { + self.address.0 <= ip && ip < self.address.1 + } +} + +impl FromStr for MapsEntry { + type Err = &'static str; + + // Format: address perms offset dev inode pathname + // e.g.: "ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0 [vsyscall]" + // e.g.: "7f5985f46000-7f5985f48000 rw-p 00039000 103:06 76021795 /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2" + // e.g.: "35b1a21000-35b1a22000 rw-p 00000000 00:00 0" + fn from_str(s: &str) -> Result<Self, Self::Err> { + let mut parts = s + .split(' ') // space-separated fields + .filter(|s| s.len() > 0); // multiple spaces implies empty strings that need to be skipped. + let range_str = parts.next().ok_or("Couldn't find address")?; + let perms_str = parts.next().ok_or("Couldn't find permissions")?; + let offset_str = parts.next().ok_or("Couldn't find offset")?; + let dev_str = parts.next().ok_or("Couldn't find dev")?; + let inode_str = parts.next().ok_or("Couldn't find inode")?; + let pathname_str = parts.next().unwrap_or(""); // pathname may be omitted. + + let hex = |s| usize::from_str_radix(s, 16).map_err(|_| "Couldn't parse hex number"); + let address = { + // This could use `range_str.split_once('-')` once the MSRV passes 1.52. + if let Some(idx) = range_str.find('-') { + let (start, rest) = range_str.split_at(idx); + let (_div, limit) = rest.split_at(1); + (hex(start)?, hex(limit)?) + } else { + return Err("Couldn't parse address range"); + } + }; + let perms: [char; 4] = { + let mut chars = perms_str.chars(); + let mut c = || chars.next().ok_or("insufficient perms"); + let perms = [c()?, c()?, c()?, c()?]; + if chars.next().is_some() { + return Err("too many perms"); + } + perms + }; + let offset = hex(offset_str)?; + let dev = { + // This could use `dev_str.split_once(':')` once the MSRV passes 1.52. + if let Some(idx) = dev_str.find(':') { + let (major, rest) = dev_str.split_at(idx); + let (_div, minor) = rest.split_at(1); + (hex(major)?, hex(minor)?) + } else { + return Err("Couldn't parse dev")?; + } + }; + let inode = hex(inode_str)?; + let pathname = pathname_str.into(); + + Ok(MapsEntry { + address, + perms, + offset, + dev, + inode, + pathname, + }) + } +} + +// Make sure we can parse 64-bit sample output if we're on a 64-bit target. +#[cfg(target_pointer_width = "64")] +#[test] +fn check_maps_entry_parsing_64bit() { + assert_eq!( + "ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0 \ + [vsyscall]" + .parse::<MapsEntry>() + .unwrap(), + MapsEntry { + address: (0xffffffffff600000, 0xffffffffff601000), + perms: ['-', '-', 'x', 'p'], + offset: 0x00000000, + dev: (0x00, 0x00), + inode: 0x0, + pathname: "[vsyscall]".into(), + } + ); + + assert_eq!( + "7f5985f46000-7f5985f48000 rw-p 00039000 103:06 76021795 \ + /usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2" + .parse::<MapsEntry>() + .unwrap(), + MapsEntry { + address: (0x7f5985f46000, 0x7f5985f48000), + perms: ['r', 'w', '-', 'p'], + offset: 0x00039000, + dev: (0x103, 0x06), + inode: 0x76021795, + pathname: "/usr/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2".into(), + } + ); + assert_eq!( + "35b1a21000-35b1a22000 rw-p 00000000 00:00 0" + .parse::<MapsEntry>() + .unwrap(), + MapsEntry { + address: (0x35b1a21000, 0x35b1a22000), + perms: ['r', 'w', '-', 'p'], + offset: 0x00000000, + dev: (0x00, 0x00), + inode: 0x0, + pathname: Default::default(), + } + ); +} + +// (This output was taken from a 32-bit machine, but will work on any target) +#[test] +fn check_maps_entry_parsing_32bit() { + /* Example snippet of output: + 08056000-08077000 rw-p 00000000 00:00 0 [heap] + b7c79000-b7e02000 r--p 00000000 08:01 60662705 /usr/lib/locale/locale-archive + b7e02000-b7e03000 rw-p 00000000 00:00 0 + */ + assert_eq!( + "08056000-08077000 rw-p 00000000 00:00 0 \ + [heap]" + .parse::<MapsEntry>() + .unwrap(), + MapsEntry { + address: (0x08056000, 0x08077000), + perms: ['r', 'w', '-', 'p'], + offset: 0x00000000, + dev: (0x00, 0x00), + inode: 0x0, + pathname: "[heap]".into(), + } + ); + + assert_eq!( + "b7c79000-b7e02000 r--p 00000000 08:01 60662705 \ + /usr/lib/locale/locale-archive" + .parse::<MapsEntry>() + .unwrap(), + MapsEntry { + address: (0xb7c79000, 0xb7e02000), + perms: ['r', '-', '-', 'p'], + offset: 0x00000000, + dev: (0x08, 0x01), + inode: 0x60662705, + pathname: "/usr/lib/locale/locale-archive".into(), + } + ); + assert_eq!( + "b7e02000-b7e03000 rw-p 00000000 00:00 0" + .parse::<MapsEntry>() + .unwrap(), + MapsEntry { + address: (0xb7e02000, 0xb7e03000), + perms: ['r', 'w', '-', 'p'], + offset: 0x00000000, + dev: (0x00, 0x00), + inode: 0x0, + pathname: Default::default(), + } + ); +} |