sysv-generator: better error reporting (#3977)

Currently in the journal you get messages without context like:
systemd-sysv-generator[$pid]: Failed to build name: Invalid argument

When parsing the init script, show the file and line number where the
error was found. At the same time, add more context information if
available.

Thus turning the message into something like:
systemd-sysv-generator[$pid]: [/etc/init.d/root-system-proofd:13] Could not build name for facility $network,: Invalid argument

1 files changed, 10 insertions, 7 deletions

diff --git a/src/sysv-generator/sysv-generator.c b/src/sysv-generator/sysv-generator.c
index 3ed8f23ff9..39821687b9 100644
--- a/src/sysv-generator/sysv-generator.c
+++ b/src/sysv-generator/sysv-generator.c
@@ -247,7 +247,7 @@ static char *sysv_translate_name(const char *name) {
         return res;
 }
 
-static int sysv_translate_facility(const char *name, const char *filename, char **ret) {
+static int sysv_translate_facility(SysvStub *s, unsigned line, const char *name, char **ret) {
 
         /* We silently ignore the $ prefix here. According to the LSB
          * spec it simply indicates whether something is a
@@ -266,15 +266,18 @@ static int sysv_translate_facility(const char *name, const char *filename, char
                 "time",                 SPECIAL_TIME_SYNC_TARGET,
         };
 
+        const char *filename;
         char *filename_no_sh, *e, *m;
         const char *n;
         unsigned i;
         int r;
 
         assert(name);
-        assert(filename);
+        assert(s);
         assert(ret);
 
+        filename = basename(s->path);
+
         n = *name == '$' ? name + 1 : name;
 
         for (i = 0; i < ELEMENTSOF(table); i += 2) {
@@ -299,7 +302,7 @@ static int sysv_translate_facility(const char *name, const char *filename, char
         if (*name == '$')  {
                 r = unit_name_build(n, NULL, ".target", ret);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to build name: %m");
+                        return log_error_errno(r, "[%s:%u] Could not build name for facility %s: %m", s->path, line, name);
 
                 return r;
         }
@@ -337,11 +340,11 @@ static int handle_provides(SysvStub *s, unsigned line, const char *full_text, co
 
                 r = extract_first_word(&text, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to parse word from provides string: %m");
+                        return log_error_errno(r, "[%s:%u] Failed to parse word from provides string: %m", s->path, line);
                 if (r == 0)
                         break;
 
-                r = sysv_translate_facility(word, basename(s->path), &m);
+                r = sysv_translate_facility(s, line, word, &m);
                 if (r <= 0) /* continue on error */
                         continue;
 
@@ -403,11 +406,11 @@ static int handle_dependencies(SysvStub *s, unsigned line, const char *full_text
 
                 r = extract_first_word(&text, &word, NULL, EXTRACT_QUOTES|EXTRACT_RELAX);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to parse word from provides string: %m");
+                        return log_error_errno(r, "[%s:%u] Failed to parse word from provides string: %m", s->path, line);
                 if (r == 0)
                         break;
 
-                r = sysv_translate_facility(word, basename(s->path), &m);
+                r = sysv_translate_facility(s, line, word, &m);
                 if (r <= 0) /* continue on error */
                         continue;