From 348e6091cb45f657dbfed656f0ba1fab8d1f7845 Mon Sep 17 00:00:00 2001
From: Jim Warner <james.warner@comcast.net>
Date: Sun, 1 Jul 2012 00:00:11 -0500
Subject: [PATCH] library: add a single vector string choice for 'environ'

In preparation for top scrollable environment display,
the new flag PROC_EDITENVRCVT was added to mirror the
existing single vector string handling for cgroup and
cmdline.

Signed-off-by: Jim Warner <james.warner@comcast.net>
---
 proc/readproc.c | 31 ++++++++++++++++++++++++-------
 proc/readproc.h |  1 +
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/proc/readproc.c b/proc/readproc.c
index 1e9d3414..63dbd5c9 100644
--- a/proc/readproc.c
+++ b/proc/readproc.c
@@ -600,7 +600,7 @@ static char** file2strvec(const char* directory, const char* what) {
 
     // this is the former under utilized 'read_cmdline', which has been
     // generalized in support of these new libproc flags:
-    //     PROC_EDITCGRPCVT, PROC_EDITCMDLCVT
+    //     PROC_EDITCGRPCVT, PROC_EDITCMDLCVT and PROC_EDITENVRCVT
 static int read_unvectored(char *restrict const dst, unsigned sz, const char* whom, const char *what, char sep) {
     char path[PROCPATHLEN];
     int fd;
@@ -690,6 +690,17 @@ static void fill_cmdline_cvt (const char* directory, proc_t *restrict p) {
  #undef uFLG
 }
 
+    // This routine reads an 'environ' for the designated proc_t and
+    // guarantees the caller a valid proc_t.environ pointer.
+static void fill_environ_cvt (const char* directory, proc_t *restrict p) {
+    int whackable_int = MAX_BUFSZ;
+
+    dst_buffer[0] = '\0';
+    if (read_unvectored(src_buffer, MAX_BUFSZ, directory, "environ", ' '))
+        escape_str(dst_buffer, src_buffer, MAX_BUFSZ, &whackable_int);
+    p->environ = vectorize_this_str(dst_buffer[0] ? dst_buffer : "-");
+}
+
 // warning: interface may change
 int read_cmdline(char *restrict const dst, unsigned sz, unsigned pid) {
     char path[PROCPATHLEN];
@@ -781,9 +792,12 @@ static proc_t* simple_readproc(PROCTAB *restrict const PT, proc_t *restrict cons
         }
     }
 
-    if (unlikely(flags & PROC_FILLENV))         // read /proc/#/environ
-        p->environ = file2strvec(path, "environ");
-    else
+    if (unlikely(flags & PROC_FILLENV)) {       // read /proc/#/environ
+        if (flags & PROC_EDITENVRCVT)
+            fill_environ_cvt(path, p);
+        else
+            p->environ = file2strvec(path, "environ");
+    } else
         p->environ = NULL;
 
     if (flags & (PROC_FILLCOM|PROC_FILLARG)) {  // read /proc/#/cmdline
@@ -890,9 +904,12 @@ static proc_t* simple_readtask(PROCTAB *restrict const PT, const proc_t *restric
         if (flags & PROC_FILLSUPGRP)
             supgrps_from_supgids(t);
 #endif
-        if (unlikely(flags & PROC_FILLENV))             // read /proc/#/task/#/environ
-            t->environ = file2strvec(path, "environ");
-        else
+        if (unlikely(flags & PROC_FILLENV)) {           // read /proc/#/task/#/environ
+            if (flags & PROC_EDITENVRCVT)
+                fill_environ_cvt(path, t);
+            else
+                t->environ = file2strvec(path, "environ");
+        } else
             t->environ = NULL;
 
         if (flags & (PROC_FILLCOM|PROC_FILLARG)) {      // read /proc/#/task/#/cmdline
diff --git a/proc/readproc.h b/proc/readproc.h
index 2bfbfb08..774fd3bc 100644
--- a/proc/readproc.h
+++ b/proc/readproc.h
@@ -272,6 +272,7 @@ extern proc_t * get_proc_stats(pid_t pid, proc_t *p);
 
 #define PROC_EDITCGRPCVT    0x10000 // edit `cgroup' as single vector
 #define PROC_EDITCMDLCVT    0x20000 // edit `cmdline' as single vector
+#define PROC_EDITENVRCVT    0x40000 // edit `environ' as single vector
 
 // it helps to give app code a few spare bits
 #define PROC_SPARE_1     0x01000000