Dynamically scale the ST_UID size to support 32-bit UIDs

While most Unix-like systems use 16-bit user IDs,
Linux supports 32-bit UIDs since version 2.6.
UIDs above 65535 are used for UID namespacing of containers,
where a container has its own set of 16-bit user IDs.
Processes in such containers will have (much) larger UIDs than 65535.

Because the current format strings for `ST_UID` and `USER`
are `%5d` and `%9d` respectively, processes with such UIDs
lead to misaligned columns.

Dynamically scale the `ST_UID` column and increase the size of `USER`
to 10 characters (length of UINT32_MAX) to ensure that the user ID always fits.

Additionally: clean up how the titlebuffer size calculation and ensure
the PID column has a minimum size of 5.

1 files changed, 7 insertions, 0 deletions

diff --git a/Process.h b/Process.h
index 4080d98c..bbdcbf66 100644
--- a/Process.h
+++ b/Process.h
@@ -278,8 +278,12 @@ void Process_writeField(const Process* this, RichString* str, ProcessField field
 int Process_compare(const void* v1, const void* v2);
 void Process_delete(Object* cast);
 extern const ProcessFieldData Process_fields[LAST_PROCESSFIELD];
+#define PROCESS_MIN_PID_DIGITS 5
 #define PROCESS_MAX_PID_DIGITS 19
+#define PROCESS_MIN_UID_DIGITS 5
+#define PROCESS_MAX_UID_DIGITS 19
 extern int Process_pidDigits;
+extern int Process_uidDigits;
 
 typedef Process* (*Process_New)(const struct Settings_*);
 typedef void (*Process_WriteField)(const Process*, RichString*, ProcessField);
@@ -337,6 +341,9 @@ static inline bool Process_isThread(const Process* this) {
 
 void Process_setupColumnWidths(void);
 
+/* Sets the size of the UID column based on the passed UID */
+void Process_setUidColumnWidth(uid_t maxUid);
+
 /* Takes number in bytes (base 1024). Prints 6 columns. */
 void Process_printBytes(RichString* str, unsigned long long number, bool coloring);