swaynag: do error checking and rename read_from_stdin

read_from_stdin not only read from stdin, but trimming trailing
newlines, so rename it to reflect this.

1 files changed, 23 insertions, 11 deletions

diff --git a/swaynag/config.c b/swaynag/config.c
index b212a0c3..5ff00bdb 100644
--- a/swaynag/config.c
+++ b/swaynag/config.c
@@ -11,28 +11,40 @@
 #include "util.h"
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 
-static char *read_from_stdin(void) {
-        char *buffer = NULL;
-        size_t buffer_len = 0;
-        char *line = NULL;
-        size_t line_size = 0;
-        ssize_t nread;
-        while ((nread = getline(&line, &line_size, stdin)) != -1) {
+static char *read_and_trim_stdin(void) {
+        char *buffer = NULL, *line = NULL;
+        size_t buffer_len = 0, line_size = 0;
+        while (1) {
+                ssize_t nread = getline(&line, &line_size, stdin);
+                if (nread == -1) {
+                        if (feof(stdin)) {
+                                break;
+                        } else {
+                                perror("getline");
+                                goto freeline;
+                        }
+                }
                 buffer = realloc(buffer, buffer_len + nread + 1);
                 if (!buffer) {
                         perror("realloc");
-                        return NULL;
+                        goto freebuf;
                 }
-                snprintf(&buffer[buffer_len], nread + 1, "%s", line);
+                memcpy(&buffer[buffer_len], line, nread + 1);
                 buffer_len += nread;
         }
         free(line);
 
-        while (buffer && buffer[buffer_len - 1] == '\n') {
+        while (buffer_len && buffer[buffer_len - 1] == '\n') {
                 buffer[--buffer_len] = '\0';
         }
 
         return buffer;
+
+freeline:
+        free(line);
+freebuf:
+        free(buffer);
+        return NULL;
 }
 
 int swaynag_parse_options(int argc, char **argv, struct swaynag *swaynag,
@@ -222,7 +234,7 @@ int swaynag_parse_options(int argc, char **argv, struct swaynag *swaynag,
                 case 'l': // Detailed Message
                         if (swaynag) {
                                 free(swaynag->details.message);
-                                swaynag->details.message = read_from_stdin();
+                                swaynag->details.message = read_and_trim_stdin();
                                 if (!swaynag->details.message) {
                                         return EXIT_FAILURE;
                                 }