Package: ccal Version: 4.1 Severity: important Dear Maintainer,
* What led up to the situation? Running ccal on a modern Linux environment with a current compiler toolchain (GCC 14/15). * What exactly did you do (or not do) that was effective (or ineffective)? Executed the `ccal` binary from an ANSI terminal emulator. * What was the outcome of this action? The terminal rendered raw ANSI attribute strings (e.g., "37;42m") as literal text because the escape sequence prefix (`\033[`) was completely dropped from stdout. Inspecting `src/cal.c` revealed a classic undefined behavior bug in the `setcolor()` function: sprintf(command,"%s3%d;4%dm",command,dos2ansi[attr&0x0F],...); Using the destination array variable (`command`) as a source argument (`%s`) inside `sprintf` is undefined behavior under the ISO C standard. Modern aggressive compiler pointer-aliasing optimizations optimize out or strip the initial token entirely. * What outcome did you expect instead? The monthly calendar and special days column should display with correctly rendered terminal background and foreground text colors. I have attached a minimal patch (`fix-ansi-sprintf.patch`) that eliminates this undefined behavior by bypassing the intermediate `command` buffer entirely, instead streaming the ANSI tokens directly to stdout using standard `fputs` and `fprintf`. -- System Information: Debian Release: forky/sid APT prefers resolute-updates APT policy: (500, 'resolute-updates'), (500, 'resolute-security'), (500, 'resolute') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 7.0.0-15-generic (SMP w/4 CPU threads; PREEMPT) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set Shell: /bin/sh linked to /usr/bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled Versions of packages ccal depends on: ii libc6 2.43-2ubuntu2 ccal recommends no packages. ccal suggests no packages.
fix-ansi-sprintf
Description: application/mbox
